Mobile user authentication

[Redan Hassoun]

Hi,
I want to make an android application which needs to serve many users , and i am looking for the best way to implement a user authentication method.
I am pretty new in developing android apps, so i am confused on choosing a good mechanism which is secure and not very hard to implement.

* I prefer identifying the user via device ID / SIM card , so the user does not need to enter username and password every time he wants to run the application.
I like the dentifying process which is performed on the Whatsapp application, where every user has his own profile by SIM card.

Can you tell me the prods and cons of this method ?
And how can i implement it ?

[Ron McLeod]

This doesn't answer your question about authentication, but the TelephonyManager can provide you the cellular device related identities:
   getSubscriberId() - returns IMSI, which uniquely identifies a wireless user
   getDeviceId() - returns IMEI, which uniquely identifes a device (phone, tablet, etc.)
   getSimSerialNumber() - returns ICCID, which uniquely identifies a SIM

These will only be present on a device which has cellular capabilities.

[ab singh]

For User Authentication you can use combination of app and server side technology.
1. create registration module, let the user register, send the data to server using xampp+php+mysql.
2. create a session like method that will save your detail in a variable (device memory) so that each time it will check user credential. if the user is logged in it will not ask to re-login.
3. while login user will enter id and password first time. send credential to server , check credential on database,if user exists with same detail. save detail in session method in device memory.
4. next time if user run the app check detail from the session variable.
5. You can also use device id and save it on server but if your app can be used by same user on other phone that there might be some problem.
for more detail Android Hive login
Tutorial point Login

[Giovanni Montano]

Redan Hassoun wrote:Hi,
I want to make an android application which needs to serve many users , and i am looking for the best way to implement a user authentication method.
I am pretty new in developing android apps, so i am confused on choosing a good mechanism which is secure and not very hard to implement.

* I prefer identifying the user via device ID / SIM card , so the user does not need to enter username and password every time he wants to run the application.
I like the dentifying process which is performed on the Whatsapp application, where every user has his own profile by SIM card.

Can you tell me the prods and cons of this method ?
And how can i implement it ?

I heard firebase is a good way to start. As semplifies a lot