Firstly, I completely disagree with this notion that young adults should be cutting off in coffees and cocktails every so often so that they can buy more expensive stuff in the long run. If incurring in these small expenditures every once in a while derives enough value for you to feel that you are leading a satisfactory lifestyle and as a result make you steer away from the big, impulsive spends (such as cars and headphones), then why not spend the extra dollar on a coffee? Even if you it every single day, at the end of the month you'll only have spent 30$ extra. If you did that every day for 2 years, you'd still only have spent an extra 730$, which is way cheaper than buying a new car. The goal for young adults should be financial independence, not to be able to spend large amounts of money in dispensable goods.
Secondly, I don't see how the fact that the app "doesn’t connect to your bank account or show depressing red info graphics". After putting in so much effort in reducing my spending, why should I have to manually input every dollar I spend into the app?
However what we were noticing was that many people (young adults in particular) had small hopes and dreams that required some amount of money that they simply didn't have. People wanted cars so they could easily get to a new job, a new musical instrument for their favorite hobby, or to take a trip somewhere they've never had the chance to go before.
It's all about how you want to spend your own money and everyone's priorities are different.
From my personal experience using mint, I usually find that the big spends are the ones that really cause a dent on my monthly budgets and honestly, from a personal finance point of view, don't see much value in tracking only the small day-to-day savings. It is necessary to have a look at the big picture to contextualize the spending.
I do feel like keep is probably a good tool for staying motivated while budgeting and getting an instant reward for something that usually doesn't give an instant reward, but even so the effort necessary to manually input every single dollar I save into the app just seems like such a commitment. To me, keep would be really helpful as a complement to the services that do connect to my bank account (in my case mint), to help me decide wether I can have the coffee I like such much or if I should stick to the free coffee available in my office.
Maybe the right answer here is to couple this app with a bank account -- so that when you say you didn't spend $3 on a coffee today, that the $3 ends up in an earmarked savings account (or at least deducted from the "safe-to-spend" balance) for that special something you're saving up for.
Either way, I think it is a tool that can be used for good as long as that assumption is understood upfront.
If you have 10x that amount of money, then your trivial expenses are also 10x more expensive. It's weekend getaways to Vegas vs a cocktail, $100 steak dinners vs a cup of coffee.
This app looks to try to teach some sort of understanding and self control in spending - which is important no matter how much money you think you have.
You'd be surprised how many people get deep in debt from trivial expenses. It's not like these people didn't want to "make more money".