What's the best iOS app for predicting flight prices and finding the cheapest days to travel?

Hopper is designed specifically for travelers who prioritize budget and flexibility. The app's core functionality is a predictive algorithm that forecasts flight and hotel prices with a claimed 95% accuracy, advising users whether to book immediately or wait for a predicted drop. A key feature for finding cheap travel days is the full-month calendar view, which color-codes dates from green (cheapest) to red (most expensive). This allows someone planning a vacation to Europe, for example, to shift their departure by a few days to save hundreds of dollars instantly. For added security, Hopper offers a 'Price Freeze' feature, letting users lock in a quoted fare for a small fee while they finalize plans.

Users report high satisfaction with the app's straightforward presentation of complex data, making price comparison less overwhelming. However, some independent tests suggest that while its predictions are often correct, the lowest prices shown are not always absolute and can sometimes be matched or beaten by direct booking or persistent searching on other platforms. The app also aggregates results from various travel sites and airlines, which streamlines the search but occasionally leads to minor discrepancies in final booking terms. For travelers without fixed dates, Hopper's visual tools and watchlist notifications provide a significant advantage in managing travel budgets.