New Service to Open Source Custom URL Schemes for iOS Developers

13 Jun

Zwapp icon 150x150From the makers of mobile app discovery service Zwapp, there comes, a new initiative which aims to open source the unpublished custom URL schemes for iOS applications. For those unaware, a custom URL scheme is a way for apps to communicate with each other and do other smart things. For example, custom URL schemes allow other apps or Web pages to call the app, trigger it and send data to it, or even transfer data between lite and paid app versions.

Apple's built-in apps like Safari, the Phone app, the Messaging app, Email and others have URL schemes included by default. Developers using the iOS SDK can built their own, too. Unfortunately, though, there isn't a well-maintained master list of these custom URLs anywhere on the Web.


Because Zwapp wants to use the custom URL schemes for app detection purposes, it needs a master list like this to better function. But instead of building up such list in private, the company has launched an open source initiative to improve inter-app communications for all iOS developers, allowing everyone to contribute and benefit from the work.

How Works

The site went live just last week, and uses an open source Mac-only tool to scan your iTunes library in order to locate these custom URL schemes. The data that is scanned is uploaded to the site and is instantly accessible to all developers. No personal or private data is scanned or made public, says Alexander van Elas, Zwapp's founder.

Zwapp app schemes

Already, over 8,300 apps had been donated to this project by the end of last week, and as of this morning, that number has climbed to 9,517.  As awareness grows, even more apps should come soon.

To access the data, Zwapp has made a JSON API available to developers. The list is also available on the website for manual perusal and searching.

In Zwapp's App

At present, Zwapp does not use the data from OneMillionApps in its iOS application, which scans your device to determine what apps are on your phone so you can share those with friends. Currently, it only detects 25-50% of the apps you have installed on its first run, and more are found as you start using the app. However, the scan results from the new service will be included in Zwapp shortly and this will lead to much better first-run scores, van Elas explains.

In the meantime, developers or end users wishing to contribute to the project can do so here.