So you want to get the first-party builds of Cheogram Android from https://mboa-dev.itch.io/cheogram and you want to be notified of updates by Obtainium instead of Mitch.

No problem, we can have Obtainium do track-only here.

First get your download page link, it will look like {{{https://mboa-dev.itch.io/cheogram/download/SOMETOKEN}}}

Enter this link into Obtainium. It will enter setup mode for an "HTML source".

custom APK link filter by regular expression: {{{javascript:void\(0\);}}}

enable "apply version string extraction regex to whole page"

enable "track only"

version string extraction regex: {{{Version (\d+\.\d+\.\d+-\d+)}}}

version extraction regex capture group: {{{$1}}}

Enter the app name too so you know which item this is in your list