I use Instagram (using manuel.subredu username) to post more or less random photos on no specific subject. I usuall try to post one photo per week using #weeklyphoto hash-tag. I use that tag for the simple reason that it was available when I decided to use it.
PixieSet
Photos from PixieSet portofolio are more curated photos. I group them by subject or event. Opposite from Instagram, PixieSet is more experimental and more in status of work in progress.
Mastodon
Following Twitter crash (yes, IMHO, is useless now), I decided I want to give microblogging a new start and decided to go with Mastodon, an OpenSource, descentralized social media service, using @manuelsubredu. I post about anything that I consider useful for sharing.