GPS Team Tracker — FAQ & Knowledge Base
What happens to your account, your teams and your encrypted positions when you reinstall Xopoz
Yes, you can uninstall and reinstall Xopoz at any time. Your account, your team memberships and all the encrypted GPS positions stored on the server survive the reinstall — they are not stored on your phone. After reinstall you log in with your e-mail and password and your account is back exactly as before.
One thing does not survive the reinstall: your team encryption keys. These keys live only on your device by design (the server never sees them) so an uninstall, a "Clear data" in Android settings, or a switch to a new phone will erase them. Without those keys, your app can still see which teams you belong to but cannot decrypt the positions of your teammates — the team appears with zero visible members until the keys are restored. Recovery takes about 30 seconds: any current member of the team scans you a "group ticket" QR code that re-shares the team key.
Xopoz uses end-to-end encryption for GPS positions inside teams. To understand what a reinstall does, it helps to know what is stored where.
The server stores the encrypted GPS positions as opaque ciphertext. It never sees coordinates and it never sees the team key. This is the core privacy property: even an attacker with full server access cannot turn the stored blobs into locations because the decryption key only exists on each member's device. The trade-off is that if every device that holds the key loses it, the data is unrecoverable from the server alone — the server cannot send you a key it never had.
For the same reason, Xopoz does not implement an "automatic backup of encryption keys to the cloud". An automatic cloud backup would require us to either escrow the key somewhere we can read it (which defeats end-to-end encryption) or guard it with a recovery secret that is just as easy to lose as the key itself. Sharing the key from another team member who still has it is the safer recovery path.
Android removes the entire app-private storage when you uninstall, and likewise when you tap Settings → Apps → Xopoz → Storage → Clear data. This wipes the device-local files and SharedPreferences, but leaves the Android Keystore master key untouched (it lives in a hardware-backed area separate from app storage).
Without the team key, your app downloads encrypted positions from the server but cannot decrypt them. The team appears in your teams list but with zero visible members. The fix is to re-receive the key from someone who still has it.
Any teammate whose phone still has the team key can re-share it with you. They open the Teams fragment in Xopoz, tap the team in question, and choose Generate group ticket QR code. The QR encodes the team identifier plus the team key. Both you and them stay in front of the phones for about 10 seconds while you scan.
On your reinstalled phone, open the Teams fragment, tap Join existing team, and scan the QR. Your app stores the team key locally (encrypted by the Android Keystore master key) and triggers a small server call to confirm membership. Decryption resumes immediately — the historical positions that already came back from the server unlock retroactively, so you also recover the recent trail of each teammate.
Each team has its own key. If you are in three teams, you need three QR scans (one per team). The QR scans can come from different teammates — whichever member of each team is closest at hand.
A team where you are the sole member — for example a personal "my devices" team you created — has its key stored only on your device. After a reinstall, that key is gone permanently and the historical positions encrypted with it become unrecoverable. The right action in that case is to delete the empty team and create a new one; positions you push from the new install onwards will be encrypted with the new key and visible normally. Before any planned reinstall on a personal team, export your trail (Settings → Export track) so the data survives in human-readable form.
If you can plan the reinstall in advance, a few short steps make recovery painless.
You will be asked to log in again. The Xopoz app does not have a "magic link" recovery flow, so make sure you have the credentials at hand or use a password manager.
For each team you care about, identify one current member who has the app working and can scan you a QR. If you are the only member of a team, plan to recreate it.
Settings → Export track produces a GPX file of your private trail history. The reinstall will not preserve this trail (it was encrypted with the old device key), so an export is the only way to keep it.
The osmdroid tile cache is wiped with the reinstall. If you depend on offline maps, pan across your area at the relevant zoom levels after the reinstall to repopulate the cache.
Moving Xopoz to a new device is functionally identical to a reinstall: the new phone has no team keys, you log in with the same account and you scan QRs from teammates to recover keys. There is one extra detail to keep in mind:
Each phone is a separate device in Xopoz. The new phone gets a new device record on first login (visible in Settings → Devices). Your account can hold several devices simultaneously, so the old phone (if still active) and the new phone both push positions independently. If the old phone is gone for good, you can delete it from the device list to keep the team display clean.
| Item | Survives reinstall | Recovery path |
|---|---|---|
| Account & password | Yes | Log in |
| Team memberships | Yes | Visible immediately after login |
| License & subscription | Yes | Restored at login |
| Encrypted positions on server | Yes | Decryptable again once team key is back |
| Shared POIs | Yes | Re-downloaded on first sync |
| Team encryption keys | No | Scan QR from a current team member |
| Local device crypto key | No | New one generated automatically |
| Private trail history | No | Export to GPX before reinstall to keep it |
| Cached map tiles | No | Pan over the area after reinstall |
| App settings & preferences | No | Reconfigure after first launch |
| Pending outbound messages | No | Re-send if still relevant |
Reinstalling Xopoz is safe but not free of friction: plan one QR scan with a teammate for each team you belong to. If you are the sole member of a team, export your trail beforehand and recreate the team after the reinstall. The architecture deliberately keeps team keys off our servers — that is the core privacy property — so the small recovery dance is the price of end-to-end encryption.