Kadera is a reminder and nudge app for iPhone. Everything it stores stays on your device. There is no account and no server behind it.
Because Kadera has no account and no server, there is nothing for us to look up at this end. When you write, it helps to include:
We aim to reply within a few working days.
A reminder didn't notify me. Check iOS Settings → Notifications → Kadera. If notifications are off, or set to deliver quietly, Kadera shows a standing notice saying so at the top of its Home screen. Scheduled Summary also holds banners back until its delivery time.
My reminders paused on their own. That is auto-pause. A fast reminder that goes unanswered for a long stretch stops asking, so that it doesn't fill up your Lock Screen. You can switch the behaviour off in Kadera's Settings → Notifications, or reactivate the reminder from its detail page.
Everything is silent while I'm away. Check Vacation Mode in Settings → Notifications. Individual reminders can be kept running through a vacation from their own detail page.
Calendar events aren't showing. Calendar access is optional, and Kadera only reads. Grant or revoke it in iOS Settings → Privacy & Security → Calendars → Kadera. An imported event is a copy, and it is not kept in sync with your calendar afterwards.
I want my data somewhere safe. Settings → Backup exports a full backup. It can also write automatic snapshots to a folder you pick, including one in iCloud Drive or another file provider. The same section imports a backup again, either merging with what is there or replacing it.
Kadera says it couldn't load my reminders. It never deletes a database it cannot read; it sets the file aside and tells you where. Most such faults are temporary, so close the app completely and reopen it first. If your reminders are still missing, import your most recent backup from Settings → Backup.
The whole app is documented inside it, and works offline: Settings → How it works.
Kadera collects nothing. See the Privacy Policy.