The five questions
Do customers repeat-purchase or rebook? Do they currently use a phone to reach you? Would a notification change their behavior? Is your website actually good on mobile already? And can you measure the difference an app would make? Five honest answers decide most of it.
The businesses that answer yes to the first three, and no to the fourth, are the textbook case for an app: a service that repeats, reached on phones, with a weak mobile site that an app quietly replaces.
When the answer is no
One-visit businesses, content-first sites, and anything where the phone call is the conversion, do not need an app. Spend the money on the mobile site, local search presence, and reviews instead. An app nobody reopens is a bill, not an asset.
There is also a timing version of no: the app idea is right but the business systems behind it, inventory, bookings, payments, are not ready. An app in front of a manual backend is expensive friction.
When the answer is yes, the cost is no longer the obstacle
The historic blocker for small businesses was a two-platform development project with a six-figure quote. A builder that turns your existing site into signed, store-ready native apps collapses that to a one-time per-app cost, and you keep owning the accounts and the decisions.
The test stays the same as it ever was: does the app change customer behavior in a way you can measure? If it does, it is worth more than it costs.