Hi Henry, I’ve moved your topic (which was originally titled ‘Slider bar for separating a single transaction into different spending catergories’) here, as there’s been some more discussion about splitting transactions into several categories in this thread & it’ll help other users find these ideas, I hope that makes sense! 
The slider idea’s a new one though, that sounds cool 
Hugo’s comment on this idea towards the top of the thread will give you some sense of the design considerations for this.
He’s also recently previewed some of the new functionality for the spending tab 
(it looks like categories will be splittable but we don’t know about transactions yet). It sounds like we’ll get some more details as the launch of the current accounts gets nearer 