In short
Speed Overlay is a free app for Android created by zuim.de Apps. And this is a perfect way to maintain speed.
Highlights
Great for maintaining speed on bike for Pokemon Go
Really easy to use app with all the features I need
Lots of configuration options
Description
Use the app to show your speed on top of other applications like google maps or similar navigation apps, that don't offer a native speed display. Features: Notification to toggle it Change the size Transparency Move it to your favourite position Use m/s km/h or mph Display accuracy Display your coordinates Hide unit name Hide notification No Advertisments Full free version without limitations
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