LnkShortener

LnkShortener is working out of the box. Simply share a link via the share
function of your browser or any other app with LnkShortener and it will
instantaneously display a shortened URL. If you have a workin
Polr installation enable the API and obtain an
API-Key. Open the Settings in LnkShortener and enter the address of your Polr
server (e.g. https://1n.pm) including the protocol (e.g. https://).
Afterwards copy and paste the API-Key to the next field and you're ready to go
with your own domain.

The App initially running with the 1n.pm URL shortening service.
You can register an account for free and keep track of
your links and use the analytics functionalities of Polr.