Start from the app's main task and the audience's vocabulary. A name can suggest an outcome or a feeling, but it should not imply a feature the app does not provide. Short words can work well in an icon or store listing, although shortness alone does not make a name memorable.
Test how a candidate sounds when spoken and how it looks when typed. Ask a few people in the intended market to repeat it after hearing it once, then spell it after seeing it briefly. Watch for unintended meanings, hard-to-distinguish sounds and words that change meaning across English-speaking regions.
Review current app store listings, web search results, domains and social profiles for confusingly similar names. Check the exact capitalization and spelling in a small icon as well as in a full wordmark. Domain availability does not establish that an app store name or trademark is available.
Keep the strongest options and document the trade-offs. Before release, verify relevant rights and registrations with appropriate professional support. Generated suggestions are useful brainstorming inputs, not legal clearance.