Some marinas in Ireland and Scotland use the Danish service Harba to manage berth bookings. For boaters the service is accessed using an app on mobile devices, and I’ve found it convenient and usable.
Like any service provider, Harba has enhanced and developed the app and a new improved version is available. Unfortunately they have not done a good job of distributing it. I found this email message in quarantine (I use and recommend MXGuarddog), and with an abundance of caution I investigated.
It turns out the message is genuine, and to upgrade you really do have to delete the old app and install a new app.
The app icons are different: the dark blue one with a circle identifies the old app that won’t work any more, and the light blue one without a circle identifies the new one.
It works with your existing username and password, but of course you’ll need to sign in once in the new app.
Harba’s website: https://harba.co