Cash App

Cash App's round-up feature works on every card purchase, automatically rounding to the nearest dollar and moving the change into savings or investments. If you spend $12.47 on coffee, Cash App saves $0.53. Those small increments accumulate without requiring a budget overhaul or habit change, and you can direct the rounded amounts to stocks, ETFs, or Bitcoin depending on your comfort level.

This approach works best for frequent card users who want a minimal-friction way to save. The round-ups are small enough that they rarely feel like a pinch, but regular spending habits can quickly add up. Cash App's strength is simplicity: one feature, easy to understand, works on everything you buy, and integrates into a payment app you probably already use.