Kind of. There's 3 options really -
1. Tuning box from someone like DTUK. Lift the bonnet, plug it in, drive and enjoy. Removeable in minutes if you need to for any reason.
2. Remap done by a tuner. You take the car to them, they download the existing software form your ECU, then upload the remapped software. Main problem with this is that if a dealer uploads new software from BMW, you'll lose the map. Reputable tuners should re-install free of charge, so it's just an inconvenience if it happens.
3. Handheld remapping tools, like the Evolve Switch or Superchips Bluefin. All the benefits of a permanent remap, but you can return to standard as often as necessary, and re-install the map yourself.
Tuning boxes are around £350 IIRC, and any tuner charging much less than £400 is probably best avoided.