Down Zero is a scorekeeping app for practical shooting training, made by Krumble Labs, the name under which an independent developer based in Peru publishes this app.
Need help? Write to krumblelabs@proton.me.
Every message reaches a person, and you can expect a reply within five business days. Down Zero is made by one developer, so it is sometimes sooner and occasionally a little later — but no message goes unanswered. Write in English or Spanish, whichever you prefer.
On your device, and nowhere else. Everything you enter — shooters, stages, passes, scores, times, championships, and settings — is stored in a database on the phone itself. The app makes no network requests, so nothing you record is ever sent to us or to anyone else.
We cannot, and we are sorry — it is worth being direct about why. Because your data never leaves your device, we never receive a copy of it, so there is no account, no server, and no backup of ours to restore from. Uninstalling the app removes its database along with it.
If you keep a full device backup with Apple or Google, restoring your device from that backup — or transferring it to a new phone — brings the app's data back with it. That backup is the only copy that exists, so if your training records matter to you, it is worth checking that device backups are switched on.
Sessions do not sync between devices. There are no accounts and no cloud, so each device keeps its own records and neither one knows about the other. Moving to a new phone works through your device backup, as above, rather than through the app.
No. The app has no export or sharing feature and provides no way to send your records anywhere, so a device backup is how you keep a copy of them.
No. Down Zero is a training aid. It does the IPSC Minor scoring arithmetic on what you enter, and its results have no standing in any match, do not replace a match's own scoring system, and should not be used to settle a result. The arithmetic can only be as correct as what you type into it.
The app is also not a safety device. Nothing in it replaces your range's rules, a Range Officer's instructions, or your own responsibility for safe firearm handling.
Delete individual records inside the app: press and hold an item in a list to delete it. Sessions, stages, shooters, and single passes all work this way, and deleting a session takes its stages, shooters, and recorded passes with it. Anything with a screen of its own can also be deleted from that screen, through the menu in the top right.
To remove everything at once, uninstall the app. That deletes its database with it. There is nothing held anywhere else that needs deleting, and no request you have to send us.
Write to krumblelabs@proton.me. What helps most: what you did, what you expected, and what happened instead. If you can, include your app version and your device model — the version is shown in the app under Settings → About.
Screenshots are welcome. Please check them before sending if a shooter's name is visible and you would rather it were not.
Down Zero is available in English and Spanish, and follows your device's language by default. You can set it explicitly under Settings → Language.
The published documents are the ones that apply: Privacy Policy · Terms of Use