Detect what was changed from ABAddressBookRegisterExternalChangeCallback
I am using ABAddressBookRegisterExternalChangeCallback to get the external changes in AddressbookBook of the user. I am using the following code to register the callback:
ABAddressBookRef ntificationaddressbook = ABAddressBookCreate();
ABAddressBookRegisterExternalChangeCallback(ntificationaddressbook, MyAddressBookExternalChangeCallback, self);
and when this callback is called then MyAddressBookExternalChangeCallback is called successfully
void MyAddressBookExternalChangeCallback (ABAddressBookRef ntificationaddressbook,CFDictionaryRef info,void *context)
{
NSLog(@"Changed Detected......");
}
I have the following questions:
- How can i detect which contacts was changed, and which action (ADD,Update,Delete) was performed on that Contact. I need to get the recordID of that contact. Is it Possible ?
Unfortunately if thats not possible then how the apps like viber, tango, watsapp gets the change information ?
- I gets the callback method called only when the app is in background if the app is terminated is there any way to get the changes notification.
Please help. Thanks in advance.
Solution 1:
I found the solution to find what was changed in the addressbook. I am not sure if its a precise one, But some how that works.
Create a Callback Notification for Addressbook:-
ABAddressBookRef ntificationaddressbook = ABAddressBookCreate();
ABAddressBookRegisterExternalChangeCallback(ntificationaddressbook, MyAddressBookExternalChangeCallback, self);
Than Add the following code when notification Occurs:-
void MyAddressBookExternalChangeCallback (ABAddressBookRef ntificationaddressbook,CFDictionaryRef info,void *context)
{
NSTimeInterval timeStampone = [[NSDate date] timeIntervalSince1970];
NSNumber *timeStamponeobj= [NSNumber numberWithDouble: timeStampone];
NSLog(@"Start Process");
NSUserDefaults *userdefs = [[NSUserDefaults alloc]init];
NSMutableArray *arraytemp = [[NSMutableArray alloc]init];
CFArrayRef peopleRefs = ABAddressBookCopyArrayOfAllPeopleInSource(ntificationaddressbook, kABSourceTypeLocal);
NSMutableArray *changedrecords = [[NSMutableArray alloc]init];
ABAddressBookRevert(ntificationaddressbook);
CFIndex count = CFArrayGetCount(peopleRefs);
for (CFIndex i=0; i < count; i++) {
ABRecordRef ref = CFArrayGetValueAtIndex(peopleRefs, i);
NSDate* datemod = ( NSDate *)(ABRecordCopyValue(ref, kABPersonModificationDateProperty));
NSDate *lastopened = [userdefs valueForKey:@"LastOpenedDate"];
NSTimeInterval datemodifiedtime =[datemod timeIntervalSince1970];
NSNumber *modifieddatenumber= [NSNumber numberWithDouble: datemodifiedtime];
NSTimeInterval lastopeddate = [lastopened timeIntervalSince1970];
NSNumber *lastopenednumber= [NSNumber numberWithDouble: lastopeddate];
if ([modifieddatenumber intValue]>[lastopenednumber intValue]) {
ABRecordRef aSource = CFArrayGetValueAtIndex(peopleRefs,i);
int recordid = ABRecordGetRecordID(aSource);
[changedrecords addObject:[NSString stringWithFormat:@"%d",recordid]];
}
}
NSString *arraystring= [changedrecords componentsJoinedByString:@","];
[userdefs setValue:arraystring forKey:@"ArrayOfChangedPeopleString"];
[userdefs setValue:changedrecords forKey:@"ArrayOfChangedPeople"];
//-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
if ([arraystring isEqualToString:@"(null)"]) {
arraystring = [arraystring stringByReplacingOccurrencesOfString:@"(null)" withString:@""];
}
NSLog(@"arraychangedstring= %@ and length = %d",arraystring,arraystring.length);
NSLog(@"Must send data to the server here for this changed people array= %@",changedrecords);
if (arraystring.length>2) {
NSLog(@"inside if");
ABAddressBookRef addressBook = ABAddressBookCreate();
CFArrayRef allSources = ABAddressBookCopyArrayOfAllPeople( addressBook );
[userdefs setValue:@"" forKey:@"ArrayOfChangedPeopleString"];
[userdefs setValue:@"" forKey:@"ArrayOfChangedPeople"];
for (int i = 0; i<[changedrecords count]; i++) {
NSString *recordid= [changedrecords objectAtIndex:i];
int nPeople = [recordid intValue];
[IntoochUtil current_function_name:@"Inside getcontactdetails - Start"];
if(nPeople != 0){
// for (CFIndex i = nPeople_start; i < (nPeople_end); i++)
// {
// NSString *reocrdid = [NSString stringWithFormat: @"Record %ld",i];
// NSLog(@"Recordid= %@",reocrdid);
NSMutableDictionary *dict = [[NSMutableDictionary alloc]init];
//common field
NSString *first_name =nil;
NSString *mid_name = nil ;
NSString *last_name =nil ;
NSString *basic_email =nil ;
NSString *basic_mobile =nil ;
NSString *other_phone=nil;
NSString *pager_phone= nil;
//personal filed
NSString *Home_email =nil ;
NSString*home_mobile =nil ;
NSString*home_address =nil;
//business filed
NSString *work_email =nil ;
NSString *company_name =nil ;
NSString *job_title =nil ;
NSString*work_mobile =nil ;
NSString *iphone = nil;
NSString *main = nil;
NSString *work_address =nil ;
NSString *home_fax, *work_fax, *other_fax =nil;
NSString *birthday = nil;
// NSString *blogs = nil;
NSString *record_id;
ABRecordRef aSource = ABAddressBookGetPersonWithRecordID(addressBook, nPeople);
// Fetch all groups included in the current source
// Getting Record id from address book
int recordid = ABRecordGetRecordID(aSource);
record_id = [NSString stringWithFormat:@"%d",recordid];
// Getting Names from address book
// CFStringRef firstName = ABRecordCopyValue(aSource, kABPersonFirstNameProperty);
first_name= ABRecordCopyValue(aSource, kABPersonFirstNameProperty);
// first_name=[NSString stringWithFormat:@"%@",firstName];
// CFRelease(firstName);
// NSLog(@"First name= %@",first_name);
NSMutableDictionary *dict_name = [[NSMutableDictionary alloc]init];
if (!([first_name isEqualToString:@"(null)"]|| first_name == nil || first_name.length ==0))
{
[dict_name setValue:first_name forKey:@"FirstName"];
}
[first_name release];
mid_name= ABRecordCopyValue(aSource, kABPersonMiddleNameProperty);
// NSLog(@"mid name = %@",mid_name);
// CFRelease(midname);
if (!([mid_name isEqualToString:@"(null)"]|| mid_name == nil || mid_name.length ==0))
{
[dict_name setValue:mid_name forKey:@"MiddleName"];
}
[mid_name release];
last_name = ABRecordCopyValue(aSource, kABPersonLastNameProperty);
// NSLog(@"Last Name= %@",last_name);
// CFRelease(lastName);
if (!([last_name isEqualToString:@"(null)"]|| last_name == nil || last_name.length ==0))
{
[dict_name setValue:last_name forKey:@"LastName"];
}
[last_name release];
NSString *dictNamestring = [NSString stringWithFormat:@"%@",dict_name];
if (!([dictNamestring isEqualToString:@"(null)"]|| dictNamestring == nil || dictNamestring.length <4))
{
[dict setValue:dict_name forKey:@"Names"];
}
// [dict_name release];
// Getting Phone numbers from address book
NSMutableDictionary *dict_phone = [[NSMutableDictionary alloc]init];
ABMultiValueRef phones =(NSString*)ABRecordCopyValue(aSource, kABPersonPhoneProperty);
NSString* mobileLabel;
for(CFIndex i = 0; i < ABMultiValueGetCount(phones); i++) {
mobileLabel = (NSString*)ABMultiValueCopyLabelAtIndex(phones, i);
if([mobileLabel isEqualToString:(NSString *)kABPersonPhoneMobileLabel])
{
home_mobile = (NSString*)ABMultiValueCopyValueAtIndex(phones, i) ;
[dict_phone setValue:home_mobile forKey:@"Mobile"];
}
else if ([mobileLabel isEqualToString:(NSString*)kABHomeLabel])
{
basic_mobile = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:basic_mobile forKey:@"Home"];
}
else if([mobileLabel isEqualToString:(NSString *)kABWorkLabel])
{
work_mobile = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:work_mobile forKey:@"Work"];
}
else if([mobileLabel isEqualToString:(NSString *)kABPersonPhoneIPhoneLabel])
{
iphone = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:iphone forKey:@"iPhone"];
}
else if([mobileLabel isEqualToString:(NSString *)kABPersonPhoneMainLabel])
{
main = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:main forKey:@"Main"];
}
else if ([mobileLabel isEqualToString:(NSString*)kABOtherLabel])
{
other_phone = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:other_phone forKey:@"OtherPhone"];
}
else if ([mobileLabel isEqualToString:(NSString*)kABPersonPhonePagerLabel])
{
pager_phone = (NSString*)ABMultiValueCopyValueAtIndex(phones, i);
[dict_phone setValue:pager_phone forKey:@"Pager"];
}
else
{
NSLog(@"%@ label is not processed",mobileLabel);
}
}
CFRelease(phones);
NSString *dictphonestring = [NSString stringWithFormat:@"%@",dict_phone];
if (!([dictphonestring isEqualToString:@"(null)"]|| dictphonestring == nil || dictphonestring.length <4))
{
[dict setValue:dict_phone forKey:@"PhoneNos"];
}
// [dict_phone release];
// Getting Fax numbers from address book
NSMutableDictionary *dict_fax = [[NSMutableDictionary alloc]init];
ABMultiValueRef faxes =(NSString*)ABRecordCopyValue(aSource, kABPersonPhoneProperty);
NSString* FaxLabel;
for(CFIndex i = 0; i < ABMultiValueGetCount(faxes); i++) {
FaxLabel = (NSString*)ABMultiValueCopyLabelAtIndex(faxes, i);
if([FaxLabel isEqualToString:(NSString *)kABPersonPhoneHomeFAXLabel])
{
home_fax = (NSString*)ABMultiValueCopyValueAtIndex(faxes, i) ;
[dict_fax setValue:home_fax forKey:@"Home"];
}
if ([FaxLabel isEqualToString:(NSString*)kABPersonPhoneWorkFAXLabel])
{
work_fax = (NSString*)ABMultiValueCopyValueAtIndex(faxes, i);
[dict_fax setValue:work_fax forKey:@"Work"];
}
if([FaxLabel isEqualToString:(NSString *)kABPersonPhoneOtherFAXLabel])
{
other_fax = (NSString*)ABMultiValueCopyValueAtIndex(faxes, i);
[dict_fax setValue:other_fax forKey:@"Other"];
}
}
CFRelease(faxes);
NSString *dictfaxstring = [NSString stringWithFormat:@"%@",dict_fax];
if (!([dictfaxstring isEqualToString:@"(null)"]|| dictfaxstring == nil || dictfaxstring.length <4))
{
[dict setValue:dict_fax forKey:@"FaxNos"];
}
[dict_fax release];
// Getting emails from address book
ABMultiValueRef email = ABRecordCopyValue(aSource, kABPersonEmailProperty);
NSMutableDictionary *dict_email = [[NSMutableDictionary alloc]init];
NSString* email_lbl;
for(CFIndex i = 0; i < ABMultiValueGetCount(email); i++) {
email_lbl = (NSString*)ABMultiValueCopyLabelAtIndex(email, i);
if([email_lbl isEqualToString:(NSString *)kABHomeLabel])
{
Home_email = [(NSString*)ABMultiValueCopyValueAtIndex(email, i)retain];
[dict_email setValue:Home_email forKey:@"Home"];
}
else if([email_lbl isEqualToString:(NSString *)kABWorkLabel])
{
work_email = [(NSString*)ABMultiValueCopyValueAtIndex(email, i)retain];
[dict_email setValue:work_email forKey:@"Work"];
}
else if([email_lbl isEqualToString:(NSString *)kABOtherLabel])
{
basic_email = [(NSString*)ABMultiValueCopyValueAtIndex(email, i)retain];
[dict_email setValue:basic_email forKey:@"Other"];
}
else
{
NSLog(@"%@ label is processed as other",email_lbl);
basic_email = [(NSString*)ABMultiValueCopyValueAtIndex(email, i)retain];
[dict_email setValue:basic_email forKey:@"Other"];
}
}
CFRelease(email);
NSString *dictemailstring = [NSString stringWithFormat:@"%@",dict_email];
if (!([dictemailstring isEqualToString:@"(null)"]|| dictemailstring == nil || dictemailstring.length <4))
{
[dict setValue:dict_email forKey:@"Emails"];
}
// [dict_email release];
company_name = ABRecordCopyValue(aSource, kABPersonOrganizationProperty);
// NSLog(@"Company name= %@",company_name);
job_title = ABRecordCopyValue(aSource, kABPersonJobTitleProperty);
// NSLog(@"Job title= %@",job_title);
NSDate *birthdate = ABRecordCopyValue(aSource, kABPersonBirthdayProperty);
NSString *birthdate_string = [NSString stringWithFormat:@"%@",birthdate];
if (!([birthdate_string isEqualToString:@"(null)"]|| birthdate_string == nil || birthdate_string.length ==0)) {
NSDateComponents *components = [[NSCalendar currentCalendar] components:NSDayCalendarUnit | NSMonthCalendarUnit | NSYearCalendarUnit fromDate:birthdate];
NSInteger day = [components day];
NSInteger month = [components month];
NSInteger year = [components year];
birthday = [NSString stringWithFormat:@"%d-%d-%d",day,month,year];
NSLog(@"birthday= %@",birthday);
}
[birthdate release];
// Getting addressess from address book
ABMultiValueRef address =(NSString*)ABRecordCopyValue(aSource, kABPersonAddressProperty);
NSDictionary *dict_address = [[NSMutableDictionary alloc]init];
NSString* addLabel;
for(CFIndex i = 0; i < ABMultiValueGetCount(address); i++) {
addLabel=(NSString*)ABMultiValueCopyLabelAtIndex(address, i);
if ([addLabel isEqualToString:(NSString*)kABWorkLabel]) {
NSMutableDictionary *dict_work_add = [(NSMutableDictionary *)ABMultiValueCopyValueAtIndex(address, i)retain];
work_address=[NSString stringWithFormat:@"%@ %@ %@ %@ %@",[dict_work_add objectForKey:@"Street"],[dict_work_add objectForKey:@"City"],[dict_work_add objectForKey:@"State"],[dict_work_add objectForKey:@"Country"],[dict_work_add objectForKey:@"ZIP"]] ;
work_address = [work_address stringByReplacingOccurrencesOfString:@"(null)" withString:@""];
work_address = [work_address stringByReplacingOccurrencesOfString:@"\n" withString:@""];
// NSLog(@"work address = [%@] and length= %d",work_address,work_address.length);
if (!([work_address isEqualToString:@"(null)"]|| work_address == nil || work_address.length ==0))
{
[dict_address setValue:work_address forKey:@"Work"];
}
}
if ([addLabel isEqualToString:(NSString*)kABHomeLabel])
{
NSMutableDictionary *dict_home_add = [(NSMutableDictionary *)ABMultiValueCopyValueAtIndex(address, i)retain];
home_address = [NSString stringWithFormat:@"%@ %@ %@ %@ %@",[dict_home_add objectForKey:@"Street"],[dict_home_add objectForKey:@"City"],[dict_home_add objectForKey:@"State"],[dict_home_add objectForKey:@"Country"],[dict_home_add objectForKey:@"ZIP"]];
home_address = [home_address stringByReplacingOccurrencesOfString:@"(null)" withString:@""];
home_address = [home_address stringByReplacingOccurrencesOfString:@"\n" withString:@""];
// NSLog(@"home address = [%@] and length= %d",home_address,home_address.length);
if (!([home_address isEqualToString:@"(null)"]|| home_address == nil || home_address.length ==0))
{
[dict_address setValue:home_address forKey:@"Home"];
}
}
}
CFRelease(address);
NSString *dictaddrssstring = [NSString stringWithFormat:@"%@",dict_address];
if (!([dictaddrssstring isEqualToString:@"(null)"]|| dictaddrssstring == nil || dictaddrssstring.length <4))
{
[dict setValue:dict_address forKey:@"Addresses"];
}
[dict_address release];
// Getting Social Networks from address book
ABMultiValueRef social =(NSString*)ABRecordCopyValue(aSource, kABPersonSocialProfileProperty);
NSMutableDictionary *dict_social = [[NSMutableDictionary alloc]init];
if (social) {
for (int i = 0 ; i < ABMultiValueGetCount(social); i++) {
NSDictionary *socialDict = (NSDictionary *)ABMultiValueCopyValueAtIndex(social, i);
NSString *twitterid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceTwitter]) {
twitterid = (NSString*)socialDict[@"username"];
[dict_social setValue:twitterid forKey:@"Twitter"];
}
NSString *facebookid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceFacebook]) {
facebookid = (NSString*)socialDict[@"username"];
[dict_social setValue:facebookid forKey:@"Facebook"];
}
NSString *linkedinid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceLinkedIn]) {
linkedinid = (NSString*)socialDict[@"username"];
[dict_social setValue:linkedinid forKey:@"LinkedIn"];
}
NSString *gamecenterid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceGameCenter]) {
gamecenterid = (NSString*)socialDict[@"username"];
[dict_social setValue:gamecenterid forKey:@"GameCenter"];
}
NSString *myspaceid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceMyspace]) {
myspaceid = (NSString*)socialDict[@"username"];
[dict_social setValue:myspaceid forKey:@"MySpace"];
}
NSString *flickerid;
if ([socialDict[@"service"] isEqualToString:(NSString*)kABPersonSocialProfileServiceFlickr]) {
flickerid = (NSString*)socialDict[@"username"];
[dict_social setValue:flickerid forKey:@"Flicker"];
}
[socialDict release];
}
CFRelease(social);
}
NSString *dictsocialstring = [NSString stringWithFormat:@"%@",dict_social];
if (!([dictsocialstring isEqualToString:@"(null)"]|| dictsocialstring == nil || dictsocialstring.length <4))
{
[dict setValue:dict_social forKey:@"SocialNetworks"];
}
[dict_social release];
// Getting Other Fields from address book
NSMutableDictionary *dict_others = [[NSMutableDictionary alloc]init];
if (!([company_name isEqualToString:@"(null)"]||company_name == nil || company_name.length ==0)) {
[dict_others setValue:company_name forKey:@"CompanyName"];
}
if (!([job_title isEqualToString:@"(null)"]||job_title == nil || job_title.length ==0)) {
[dict_others setValue:job_title forKey:@"JobTitle"];
}
if (!([birthday isEqualToString:@"1-1-2001"]||[birthday isEqualToString:@"(null)"]||birthday == nil || birthday.length ==0)) {
[dict_others setValue:birthday forKey:@"BirthDay"];
}
NSString *dictothersstring = [NSString stringWithFormat:@"%@",dict_others];
if (!([dictothersstring isEqualToString:@"(null)"]|| dictothersstring == nil || dictothersstring.length <4))
{
[dict setValue:dict_others forKey:@"OtherInfo"];
}
[dict_others release];
[dict setValue:record_id forKey:@"RecordID"];
//This NSLog(@"Value for Dict is========= %@ =========",dict);
NSString *namedictionstring = [NSString stringWithFormat:@"%@",dict_name];
NSString *emaildictstring = [NSString stringWithFormat:@"%@",dict_email];
NSString *phonedictstring = [NSString stringWithFormat:@"%@",dict_phone];
// NSLog(@"name dict length= %d email dict length= %d phone dict length = %d",namedictionstring.length,emaildictstring.length,phonedictstring.length);
// [array_addressbook addObject:dict];
if (phonedictstring.length >3) {
[arraytemp addObject:dict];
}
else
{
if (emaildictstring.length>3 && namedictionstring.length) {
[arraytemp addObject:dict] ;
}
else
{
NSLog(@"Contact is not valid= %@",dict_name);
}
}
[dict_name release];
[dict_phone release];
[dict_email release];
[dict release];
[company_name release];
[job_title release];
/* CFRelease(firstName);
CFRelease(midname);
CFRelease(lastName);
CFRelease(jobtitle);
CFRelease(birthday_c);
CFRelease(companyname);*/
// }
}
}
NSString *json_array_string = [arraytemp JSONRepresentation];
[IntoochUtil current_function_name:@"Inside getcontactdetails - End"];
NSLog(@"Json String To send= %@",json_array_string);
if (allSources) {
CFRelease(allSources);
}
if (addressBook) {
CFRelease(addressBook);
}
}
else
{
NSLog(@"This is empty.... nothing to perform");
NSMutableArray *arrayofdeletedpeoples= [[NSMutableArray alloc]init];
ABAddressBookRef addressbook = ABAddressBookCreate();
CFArrayRef allPeoples= ABAddressBookCopyArrayOfAllPeople(addressbook);
NSMutableArray *arrayofrecordIDCallback = [[NSMutableArray alloc]init];
int count = CFArrayGetCount(allPeoples);
for (int i =0; i<count; i++) {
ABRecordRef aSource = CFArrayGetValueAtIndex(allPeoples,i);
NSString * recordid = [NSString stringWithFormat:@"%d",ABRecordGetRecordID(aSource)];
[arrayofrecordIDCallback addObject:recordid];
}
NSLog(@"arrayofrecordIDCallback = %@ and count= %d",arrayofrecordIDCallback,[arrayofrecordIDCallback count]);
NSMutableArray *arrayofallrecordids = [userdefs valueForKey:@"AllRecordIDSBackGround"];
NSLog(@"arrayofallrecordids= %@ and count= %d",arrayofallrecordids,[arrayofallrecordids count]);
for (int i=0 ; i< [arrayofallrecordids count]; i++) {
if ([arrayofrecordIDCallback containsObject:[arrayofallrecordids objectAtIndex:i]]) {
}
else
{
[arrayofdeletedpeoples addObject:[arrayofallrecordids objectAtIndex:i]];
}
}
NSLog(@"Array of deleted peoples= %@",arrayofdeletedpeoples);
[arrayofdeletedpeoples release];
[arrayofallrecordids release];
[arrayofrecordIDCallback release];
if (allPeoples) {
CFRelease(allPeoples);
}
if (addressbook) {
CFRelease(addressbook);
}
}
//-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
[changedrecords release];
[userdefs release];
[arraytemp release];
NSLog(@"Ends Process");
NSTimeInterval timeStamptwo = [[NSDate date] timeIntervalSince1970];
NSNumber *timeStamptwoObj = [NSNumber numberWithDouble: timeStamptwo];
NSLog(@"Time Difference= %d",[timeStamptwoObj intValue]-[timeStamponeobj intValue]);
}
Solution 2:
Yes thats true that you can not get specific notification on Phonebook changes. You will need to synch your data when callback notification fire.
void MyAddressBookExternalChangeCallback (ABAddressBookRef ntificationaddressbook,CFDictionaryRef info,void *context)
{
NSLog(@"Changed Detected......");
// synch data
}
The apps like viber, tango, watsapp also does the same thing but in Background thread.
If the app is terminated, then you will need to synch data when app gets started like in didFinishLaunchingWithOptions.
Solution 3:
As far I know, you can't tell what are the difference - I bumped to this problem myself.
My solution was:
I had a local Core Data based address book, and every time I got this notification, I ran a background thread that synchronised the data, and notify in the end all the changes.
Solution 4:
During the first time, I am dumping all the data in local database using sqlite, then on external change I am dumping new data from contacts database in dummy db in sqlite, then firing big long compare query based on what has changed. In our case, main focus was on phone numbers and name. Once you get change update that in your contacts db in sqlite. I think even whatsapp is doing something similar. I checked the time taken to reflect the changes by whatsapp and our app almost are similar. Actually, my app is 2 secs faster than whatsapp in terms of reflecting changes. Hope this will help.