Please use the following Google+-Community for questions and discussion: Buddy-Tracker
There you will also get some more information and a link to the beta-version.
Integral part of the Buddy-Tracker is a GPS-Tracker / -Logger that records the own locations and stores them into a local database. Those data can also be displayed on a map.
Additionally markes for personal locations can be stored that can be used as navigation-targets or markers on the map and also can be shared with friends.
A special feature to save energy is the activation of position-recording according to the recognized activity (walking, running, on bicycle, ) as the activitiy-detection uses less energy than the GPS.
The current position can be saved to the local database as a single marker or can be shared with friends.
But Buddy-Tracker can also send the newly recorded positions to the activated buddies at regular time-intervals.
The transmission is either in clear-text for buddies without an installed Buddy-Tracker or in a machine-readable version that the Buddy-Tracker can readn an then process.
For transmission there are several options:
SMS: Either in cler-text or as a data-SMS that can be processed by the Buddy-Tracker
E-Mail: Either sending in clear text, or send and receive in data-format with buddies with installed Buddy-Tracker.
Shared Folder: The Buddy-Tracker writes to a folder in the local storage of the device. That folder is then synchronised with the buddies over the internet by a 3rd party software. When that software synchronises new messages into that folder, the Buddy-Tracker reads and processes them accordingly. This was tested with Sync (alias Bittorrent-Sync) and SyncThing.
The main idea is the lack of a central server that holds all location data shared by the Buddy-Tracker. Every group of friends that wants to share position-data chooses a transmission-method. The data is then shared only between them and nobody else. The security and privacy is therefore only dependent on the reliability of that friends.
The messages itself are not encrypted yet that is an option for a future release. The SMS- or eMail-Providers might be able to read the messages. But the transmission itself can be considered secure.
That also holds for those synchronsisation-software. The transmission between the friends is encrypted. But the members of those groups can read all messages in clear-text.
The Buddy-Tracker uses the following permissions:
AUTHENTICATE_ACCOUNTS, READ_SYNC_SETTINGS, WRITE_SYNC_SETTINGS
For controlling the sync-adapters for sharing the positions by mail. This are the settings you will find in the Android-Settings at Settings/accounts/Buddy-Tracker eMail.
For sending and receiving of mails and the map data from Google-Maps.
Self explanatory. ;-)
To determine if the device is connected to the internet.
For im- and export of the data from the local database to SD-Card.
- For writing to the shared folder if using that option.
- For Android < 5.0 also for im- and export of position-data from the local database. Later Android Versions have functions that don't need this permission any more.
For acces to Google Maps for the map-display.
For sharing the data by SMS