I just want to know if there are the possibility to use Sinch for android with my personal login, and avoid to use the Parse package. I want to manage all the info only from my database, because is connected to a web application too, and there they don't use the Parse package
Yes it is, Sinch doesn't really care who you log in with (we trust that you have security on your app), you can either add the app secret in the app and start the client with any username you want (not recommended) or sign a ticket described here https://www.sinch.com/docs/voice/android/#applicationauthentication
The only thing that is important is that the username is unique for a user