Pipilo (a Fediverse/Mastodon app with horizontal timeline) is participating in #IndieAppSales.
Until December 5 you can get discounted price using one of the following codes:

INDIE25 to get one time purchase for $19.99 instead of $29.99.
INDIE25YEAR to get one year subscription for $6.99 instead of $9.99.

Redeem at https://apps.apple.com/redeem?ctx=offercodes&id=1584544719
App Store page https://apps.apple.com/us/app/pipilo/id1584544719