Android Question What libraries to use?

[carchek]

Hello, a client of mine asked me to create an app which will include:
- User registration & Add to friends (this is important)
- User 1 who is a friend of User 2 will send him a "message" and User2 gets a notification sth like:"I want to buy you a Ferrari!". If user 2 clicks yes user 1 will be notified about the agreement.

Any ideas for what libraries to use?
Thanks!

Regards,
G

 

[KMatle]

A server (with php & MySql) or B4J

Libs:

OKHttpUtils, OKHttp to call the scripts (registration, add, buy, etc.)
Firebase Notification
Some helpers like JSON, StringUtils, ByteConverter

Use the search for "Registration". This will give you some examples (and see my signature).