How do I find out if an app depends on a single outside service to work?

Ask for the architecture in plain terms: where the app is hosted, who sends its messages, who handles sign-in, who processes payments and where its data comes from. Then ask the developer, not only the seller, to mark which of those have no substitute today. The answer shows where the app is most exposed.

Check the paperwork against the list. Monthly invoices and card statements often reveal services nobody mentioned. Read the terms on the critical ones to see whether the provider can raise fees, limit usage or end access. If the app uses an unofficial connection to another product, ask what happens if that connection is closed.

Finally, test the weak spots. Ask a technical adviser to review the code for hard-wired dependencies and to estimate the work needed to switch. Ask when the app last had an outage and how the seller handled it. If one service carries most of the app, factor that into your questions about terms and protections, and ask your lawyer how the sale agreement can address it. Ask too whether the seller has ever been warned by a provider about misuse or limits. A past warning shows how the relationship works in practice, and it helps you judge how much attention that service will need.

Key takeaways

• Get a full list of outside services and who pays for each.
• Compare the list with invoices and card statements.
• Ask what the backup is for every service with no substitute.
• Have a technical adviser review the code for hard-wired links.