I want to ask recommendations for apps for a given purpose, e.g., managing bank account information. I know my questions won't fit the main site. Where can I have more luck for these questions, within SE network or outside it (e.g., some subreddits at Reddit, some Android forums)?
This site is for questions asking for recommendations of software to accomplish a particular task, that is, “what software can I use to do …?”.
It further adds
Good software recommendation requests have two components:
- A purpose — a task to accomplish, a user story
- Some objective requirements — a minimum set of features
An asker there is supposed to follow the question quality guidelines laid down at What is required for a question to contain “enough information”? It will let you understand what appropriate information should your question must have. Unclear question or info deliberately held down by asker (due to uncertainty often) makes a question good candidate for closure and/or downvote and/or it may not receive other users' attention, let alone helpful suggestions as comments or answers.
In case of further queries, use their Meta. As expected, they also have an official chat room with at least one moderator or an experienced user often available there. They may prove to be helpful if clarification may be too less of a thing to ask on meta.
As for the sites outside the Stack Exchange network, the answers here may help: Where can I ask questions that aren't Android Enthusiast questions?