Is this the correct layout to detect iBeacons with AltBeacon's Android Beacon Library?

This worked for me: "m:2-3=0215,i:4-19,i:20-21,i:22-23,p:24-24"

I don't think you need to match the 4c00 part because that is the manufacturer id, so you can probably leave that off and start with m:2-3=0215 Everything else looks right, and it seems to work.

You can download the iBeacon spec (click "Download Artwork and Specifications").

In the current version the Company ID must be 0x4C00, and the beacon type must be 0x0215. All other fields are required, and as you specified.

So yes, you are exactly correct and it will detect all compliant iBeacons.

OT: It also specifies that the advertising interval must be 100ms, but I seriously doubt all iBeacons stick to that.