Hi, I have one. You can get a mobile, purse and lipstick but not a lot more than that. They are fun little bags with jeans / t-shirt as less structured than Kelly or Birkin. They also come in lots of different colours (I have a blue jean one).
I have a Vespa TPM which is the same size and shape as the Evelyne TPM. I bought it because of the color - cyclamen - and I adore it but it is tiny. I can fit my phone, small wallet and lipgloss with no problems.
Don't use it a whole lot but I have a 9.5 month old baby so not the most practical bag to carry at the moment! If I'm going out somewhere special then I'll wear it though as its the only Hermes bag I have at the moment...and probably for a looooonnnggg time to come as all my money seems to be going on daughter these days (nearly 40 pounds on a baby sledge as over a foot of snow where I live!). Do love the little bag though...
I have Vespa and Evelyne TPMs You can actually get a bit more into the Evelyne because the toggle takes up space on the Vespa.
I don't use them a lot, but when I need to carry just a bit, I love them. Adn strap is plenty long for cross body.