Best app ideas for startups

The best startup app ideas aren't the flashiest — they're the ones that remove a painful, repeated task for a specific audience willing to pay. Think niche vertical CRMs, booking and reminder tools, micro-marketplaces, and anything that turns a manual spreadsheet workflow into a product.

Validate before you build

Pick one narrow audience, describe the outcome in one sentence, and try to pre-sell it before writing a line of code. If people won't give you an email for it, they won't pay for it.

A recurring winner: tools that connect ad spend to real revenue. Every business running paid acquisition wants to know which campaign actually made money — most still guess.

Running paid ads to generate leads? Calculate your real ROAS for free, or see how Fennec ties every euro of ad spend to the deals you actually close.