That seems strange... though I am not an app developer (I do web development).
At its most basic level, analytics is really just about sending requests to the Adobe Server... then having the server process that data...
In theory, if you can understand the format in which to send data for each type of call / interaction, essentially you should be able to send data (even if each request has to be manually built in your apps)... the SDK really just does a lot of the heavy lifting... (not that I am saying you should run out right now and manually code everything... that would take a lot of work to ensure everything is properly formatted).