This is a chicken-and-egg problem. Until enough websites are using Indieweb standards to publish content, it will remain a niche.
This makes the Indieweb necessarily a fairly tech-centric space. However, I don't believe that this makes it less valuable. The Indieweb is a new technology, though it happens to be built on top of some very old ones. New technologies are always inhabited by tech types at the beginning.
I think it's not a problem for non-IndieWeb users to read IndieWeb pages though. Most often they won't even notice it's an IndieWeb site, when they come there by accident (e.g. a search or link from somewhere else).
The first things I did this year was to create a media endpoint for my Micropub server. It works by uploading files to BunnyCDN via their storage API (great service and easy API!). However, now that I have this endpoint, I would also like to use it. It seems that there is a lack of clients that support uploading media to the media endpoint and then returning me the correct URL. I can use Indigenous to upload photos from my phone, but it seems like other file formats aren't supported. How am I supposed to create posts with audio or other files? Also Micropublish (the client I usually use on PCs) doesn't seem to support media at all.
Can someone please give me a tip, which client I should use or do I need to develop my own? Thanks!
Please also remind: My operating system are Linux, Windows and Android. Clients for macOS or iOS are pretty useless to me.
Update: Kristof De Jaeger replied to this post and promised some new features for Indigenous on Android. Thanks a lot! I'm still in search for a desktop solution though. I thought a bit about it and will probably create a basic web interface that allows me to upload any file until there's better support in other Micropub clients.
Thanks for your tip to take a look at the post by Steve Layton! Unfortunately I'm not using micro.blog currently and rather want my setup to be self-hosted as much as possible. To do that I recently also started receiving webmentions myself instead of relying on webmention.io. It's not that I don't like these services, it's more that I strive for full control over my setup.