Last updated: 8 September 2026. This page covers HABITAT and JENDRALLEK.
Write to me
I answer everything myself. Usually within two to three days — weekends can take longer, because I work shifts alongside this. There is no telephone number for general contact; email leaves more room to sort things out properly.
What helps me: which app, which phone, and what you did just before it went wrong. One screenshot beats three paragraphs.
The questions that come up
Do I need to sign up for HABITAT?
No. The map works without an account, without a name, without an email address. You only need an account if you want your tours to keep counting in JENDRALLEK.
How do I turn off location?
In the phone's settings, under the relevant app. The map still works afterwards — you just lose the blue dot, and “what is nearby” can no longer be worked out.
How do I get the map without a network?
In HABITAT, download an area to the phone beforehand. The map then works where there is no signal. How much space it needs is shown before you start.
How do I delete my account and my data?
In JENDRALLEK: Profile → right at the bottom → delete account. That removes the account and everything attached to it in one step. HABITAT has no account — there, deleting the app is enough.
Where is my health data kept?
On the phone, and only there. Illness, pain, cycle and journal are never transferred, not even to sync between two devices. What is stored in the cloud is listed in the privacy policy for the apps.
The app crashes or freezes.
Tell me which phone and which iOS version. I build both apps myself and can usually reproduce the fault if I know what happened just before.
A place on the map is wrong
The points come from OpenStreetMap — a map everybody contributes to. If a pull-up bar is missing, or a farm shop that closed is still listed, the app is not at fault; the entry is. And you can correct it yourself: sign in at openstreetmap.org and edit it.
How quickly that arrives varies: the app fetches the points fresh, so a correction is usually there the next day. The map underneath is pre-rendered and refreshed less often — there it can take a few weeks.
Privacy and legal notice
What the apps do with data is set out in the privacy policy for the apps. For this website, see the website privacy policy. Address and controller are in the legal notice.