Phone not inserted properly into dock, this is just a demonstration. :)

When placed in dock:
Turn off WiFi
Turn off Auto rotate
Turn on GPS
Brightness 100%
No screen timeout (35791 minutes roughly equals 24 days)
Speak "Bike mode"
Start bike app (MapMyRide)

When removed from dock:
Turn on WiFi
Turn on Auto rotate
Turn off GPS
Automatic brightness
Screen timeout 1 minute
Speak "Leaving bike mode"

Apps used:
Modified AnyTag forum.xda-developers.com/showthread.php?t=2122019
Tasker

Materials used:
Garmin GPS holder from ebay
No-name case from ebay
NFC-sticker (NTAG203)
Some super strong double sided tape
Some spare parts lying around the house.
Total cost: around 100SEK (15USD)

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