The solution on Android: Install Kiwi browser, install nos2x, import your privkey and finally access to Anigma, Astral, Yosu or whatever you want to login from extension. Writting this from Astral using no2x installed on Kiwi browser in my Android....
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I just simply use Astral.ninja from my phone browser.
Did you type your privkey in astral directly? Oh, that is reckless...
Here is some information on how to do it safely, read all about it.