I'm rooting to get access to my own data (typically in sqlite databases in protected /data/data partition). Then I feed it into HPI (Human Programming Interface) [1], and from that it gets into my plaintext search system [2] or promnesia [3]
[1] https://github.com/karlicoss/HPI#readme
[2] https://beepb00p.xyz/pkm-search.html#personal_information