It should be enabled by default as far as I know.
Check out the lower left hand corner in my screenshot. Mine is currently showing '--' because I'm sitting at my desk at work, not moving.
If it's not enabled, go into Settings > Navigation Settings. Under 'Driving Options' heading, enable "Speedometer".
These instructions are for Android. For iOS, I have no clue without having one of those devices in front of me.
https://uploads.tapatalk-cdn.com/201...c811fdc94d.jpg
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