Mean Velocity is an Android app that shows mean (average) speed and direction over several time periods. Mean Velocity can be used for sailing, flying, biking, hiking, kayaking or driving.
The displayed averaged time periods are over the last 10 seconds, 1 minute, 10 minutes, 1 hour, 1 day and 1 week. Speed and direction can be shown in metric or knots and nm.
Speed and direction can be displayed two ways: Net and Average. Net speed and direction is as the crow flies, from the start of each time period to the end of each time period. Average speed and direction is how far you have travelled in that time period, like an odometer, all along the wavy track.
If a mapping app is installed on your phone such as OsmAndroid, tapping a time period label will create a standard GPX format track file then open it in the mapping app to show where you have been.
Mean Velocity is not yet on Google Play store because I have not jumped through all of the hoops, a long and tedious business. It is here as a zip file and has to be sideloaded. To sideload the file, download and unzip it, save the apk file on your phone (probably Downloads folder), use a file browser on your phone to find the apk file, click it to install. You may get a security warning and have to give permission to open files not from Google Play.