Question

Is IMSI number unique for each phone ?

I want to know the answer with respect to Android.

Please help.

Answer 1

Wikipdia:

An International Mobile Subscriber Identity or IMSI (play /ˈɪmziː/) is a unique identification associated with all GSM and UMTS network mobile phone users.

Not all android devices are on GSM or UMTS. So I would guess that the ones that don’t use those networks aren’t going to have any value at all for IMSI. But I would be really really carful relying on something like that to be unique. I’ve found that different manufacturers/carriers sometimes put the same # as the value on every device for some of the supposedly unique IDs. Which will cause you major headaches if it turns out that there are thousands of devices out there using the same ID.

That being said, I have no experience working specifically with IMSI so this is just my guess.

Edit: there is no one end all be all “correct” value to use as unique ID as far as I am aware. Here are some links that can give you some ideas though:

Is Secure.ANDROID_ID unique for each device?

Is there a unique Android device ID?

If possible I think you are better off generating your own UUID and storing it yourself. But this of course means that it won’t persist through uninstallation of your application (or through SDcard wipe if you choose to store it there)