This article explains what a microapp is.
A microapp is a minimum viable product (MVP) app focused on a single user task. It can be delivered across platforms as a Web app through a simple link requiring no installation (zero-install).
Some argue that simple mobile or desktop apps also qualify. But the consensus seems to be that anything requiring a download or installation process is not a microapp.
Have you ever used an online tool to validate a block of JSON or convert a graphic file from one format to another? How about simply typing a formula into the search bar and calling up the calculator in your browser? Then you've used a microapp.
A microapp should be delivered as a browser link. This can be via a domain link or an internal link. The internal link could be to the main page of a server or a folder on a shared server. In most cloud-based organizations you can usually host a static Web app on bucket. For public facing sites you could either host microapps as a home page, in a folder, on a subdomain or even link to them running on a third party server.
Single page app
A microapp should be a single page Web app. As soon as you add a tab for a second feature it is no longer a microapp. Before adding a second feature to the existing app, consider making that second feature its own microapp.
Dialog boxes and info popups are allowed. But try to keep the user interface as simple as possible.
Scrolling is also allowed. The UI does not have to be confined "above the fold." But the app itself should still be focused on just doing one thing.
Works on mobile
The reason microapps are browser-based is to make them available cross-platform. This includes mobile. The user interface of a microapp should be responsive to whatever platform it is being run on.
Microapps are great for building internal tools. If everyone is behind a firewall you can reduce the complexity of the design even more by not having to bother with signup, login, administration or authorization screens.
In order to keep microapp design as simple as possible, supporting every browser for an MVP may prove to be too much effort. Focus on one desktop browser and the more popular mobile browsers. For an internal tool you can politely explain that officially you only support certain browsers.
Ideally a microapp should be easy to use with little or no instructions. But you could generate and monetize traffic by linking to a handy online user guide.
In this article you learned that microapps are single page, zero-install web apps focused on only doing one task. They work across platform and require little to no documentation. They can be public facing utility apps or internal tools.