What about having a tool in the app to show how the rest of your month could look financially if you made a big spend. You put in the value of what you want to buy and it gives you feedback and advice.
You currently have £180 until payday in 10 days, a nice £18/day, this is £3 above you average daily spend. If you buy these £80 jeans you will be left with £10/day. This is £5 below your daily average and you will really have to focus on careful budgeting and may miss out on something else or raid your savings.
What do you think?