There is already forked version named Fossify (hope it will be renamed soon). But for some time I switched to Clock You, Material Files, Aves, OpenCalc, QUIK. Only Dialer is probably unreplaceable right now.
F-Droid
F-Droid is an installable catalogue of FOSS (Free and Open Source Software) applications for the Android platform. The client makes it easy to browse, install, and keep track of updates on your device.
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Koler is decent if not perfect. I really like the interface though :)
Edit: https://www.f-droid.org/packages/com.chooloo.www.koler/
Koler can't block spam incoming numbers or I missed something?
Was that a feature of simple dialer? There's a separate call blocking app but I haven't played with it and tried to make it work, not sure if it might be useful to you. You might have to use it as your phone app
https://www.f-droid.org/packages/dummydomain.yetanothercallblocker/
Aves Libre is amazing and I wish I switched from Simple Gallery ages ago. It's better in almost every single way*. It's also stupidly fast in comparison to Simple Gallery. Gallery could take twenty to thirty seconds to finish background loading (and when it did it'd shunt you back to the first picture you opened if you were in the image viewer), and a full library refresh could take a minute or more before new images show up. Aves loads basically instantly and doesn't miss a single thing.
^(* Aves doesn't have Gallery's editing capabilities, but if you don't need them or are willing to download a separate app it's perfect.)
What's the news?
Some big company bought them. Apparently they have a tendency to weigh down their apps with telemetry and ads.
You apps or Fossify fork else u will have to go with apps from multiple authors (as others mentioned).
Goodwy apps