A TOEFL toolkit needs more than one app, because no single app does all four sections well. Here's a setup that actually covers everything: ten real apps, each doing a job the others don't.
Vocabulary first. Anki handles it with spaced repetition, still unbeaten for academic word lists. Quizlet gives you shared TOEFL flashcard sets plus matching games for when drilling gets dull. Memrise is the listening heavy option, with video clips of native speakers that double as TOEFL listening practice.
For structure: Notion becomes your study HQ, with section targets, a practice test log, and a countdown to test day. Google Calendar turns good intentions into scheduled blocks, because a TOEFL study plan app only works if the sessions actually happen. Duolingo keeps daily English exposure alive with streaks that guilt you into opening it.
Then the specialists. Busuu offers structured English courses with writing corrections from native speakers, which quietly doubles as writing practice. HelloTalk connects you with native speakers for language exchange, and regular conversation is the cheapest speaking practice that exists. Magoosh has dedicated TOEFL prep with video lessons, one of the few big names built specifically for this test. The BBC Learning English app gives you free, high quality listening material with transcripts, perfect for shadowing.
Here's what's missing from all of them: none tells you what to do on week five, day three. That's the difference between a pile of apps and a plan. Run three or four of these for daily reps and let a structured schedule decide the sequence. The 8-week study plan at internationalstudyhelp.fyi does that sequencing, built around your target TOEFL score.