In my case I had to build a system where it pulls from particular services (Dropbox, Box, Google Drive, Gallery, etc) or takes a picture from the camera. That is pretty straightforward with intents and you can either show every available app or specify exactly what other apps to allow. Also, we added an intent receiver so any app can share into ours. I have tested it across about 20 devices and have had 0 issues with the inter-app intents. The camera took more work but there are lots of libraries out there to solve the problems (mainly: where to store the file generated by the camera cleanly in all cases). Gallery also causes some issues because various vendors have re-implemented the gallery in non-standard ways, and remote URLs for Picassa or Google+ need to be dealt with, but it's not too bad.
If you are writing good quality code, fragmentation is completely overblown.
Android has been a discussion for us - it has Intents, so at least there is a baseline for doing inter-app communication, but it's still not as good as it could be.