Hello,
i just created my account to be able to reply to this.
I highly recommend looking into the app Linux Deploy
I started with the suggested approach here but I struggled a lot with fixing all the compilation errors and it was very slow on my Samsung Galaxy S5. Also I forogt the wake lock and all the time my mobile CPU went to sleep. But in the end it was running. But other issues with the bluetooth and so on made me crazy so I started this evening with Linux Deploy and the Homeassistant Server is already running.
Long story short : Linux Deploy is worth a try.