Peter, Will it interact with web published FM? I so, why not a browser-based solution instead of "app" (altho HTML5/CSS/JS is more app-like everyday!)?
FMGo does not work on Android, so your options narrow if you need more than one mobile platform.
Tell us more?
An NDA would be required to obtain details, but here is a brief:
1. Data interaction to and from the FM server to obtain up to date information.
2. Ability to receive 'alerts' based on this data, so that no matter what the user is doing, they are informed as soon important information arrives.
3. Ability to "call" contacts that appear in a database. "Calling" could be phone, email, facebook messenger, Skype etc- whatever interfaces are available should be made available.
There may be two variations (either two separate apps or two within one) and it would be preferable to find someone who can do both platforms.