Eevee is one of the most interesting Pokemon characters. Not only is it ridiculously cute, but it doesn't have a defined evolution path - and some of the Eevee evolutions have been the best Pokemon to take into battle - like Vaporeon. 

Right from the outset, Pokemon Go has offered a number of Eevee evolutions, expanding to five when the Johto region was added.

Eevee is something of a rare Pokemon, so it's always worth catching for the candies, if not to evolve then to power-up. Of course, you'll also need 25 candy to make each of these evolutions. 

Here are the Eevee evolutions that are available and the codename you need to choose what they turn into:

  • Vaporeon - Rainer
  • Jolteon - Sparky
  • Flareon - Pyro
  • Umbreon - Tamao
  • Espeon - Sakura

Here's all you have to do:

  1. Open up your Pokemon collection and find an Eevee that's spare.
  2. Change the name from Eevee to the codename - so that's Sakura (for Espeon) or Tamao (for Umbreon) for example - by tapping the pencil next to that character's name.
  3. Hit the evolve button and your Eevee will change into the evolution of you choice

If you don't change the name, the Eevee will evolve into any of the forms that are available in Pokemon Go: Vaporeon, Jolteon, Flareon, Umbreon and Espeon.

But what are these names you have to change? They are the names of the Pokemon owners, dug out from Pokelore. So, for example, Espeon was Sakura's, and one of her older sisters is Tamao, who owned Umbreon.

The original Eevee evolutions – Sparky, Rainer and Pyro – that you'll need to control evolution to Jolteon, Vaporeon and Flareon respectively, again come from the Eevee brothers in Pokemon anime.