Nice idea, this reminds me a bit of a similar company Thrive in Canada, who have a slightly more built out service.
I particularly like this idea if employers (at least partly) match contributions. This seems like one of the better ways to enable investing / saving before the user even sees the money.
Those fees tho 
Does anyone know of any similar companies in the UK?
Concept is good and they seem to be executing well. Fees are a bit high but Freetrade has made me very bias!
Would I use the service, no. But anything that encourages people to save is a good idea.
I thought this as well but then I saw their fee drops by 50% for people coming via their company payroll, and that discount is then valid for the life of the account.
Currently raising round 2 on Seedrs, seems they now have the team and partnerships to execute, curious to know what potential investors here think of Smarterly