Show HN: Always on GPS logger

5 points·conroe64··2 comments

An android app that logs GPS coordinates periodically to an encrypted database directly on your phone, so you can track and review where you have been throughout your life.

http://www.rareventure.com/ttt_manual/manual.html

http://play.google.com/store/apps/details?id=com.rareventure.gps2_trial

Please give any criticism you have to offer.

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From the Google Play Store: "The data is encrypted using 256 AES keys and can be password protected."

Are you sure that you don't mean that it is encrypted using a 256 bit AES Key?

And I imagine that the private key is stored on the device?

The reason for multiple AES keys is because the gps points are optionally password protected, but I didn't want to save the password anywhere on the file system, and I wanted the app needs to be able to store and encrypt points after a reboot without forcing the user to reenter their password.

I solved this issue using a pair of RSA public/private keys that are stored in internal storage. The private key is then encrypted by the password whereas the public key is not. So what happens is that on reboot, a random AES key is created, encrypted by the public RSA key and stored in a table. Then, this is used to encrypt any future GPS points until a further reboot. (I didn't want to use the RSA key directly due to efficiency concerns and the lack of a good padding mechanism within the library)

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