Whether you already speak some English or are just starting out, you’ve probably got a powerful tool to help you reach the next level of proficiency: your phone. But with so many phone apps for English learners, how do you find the right app for your needs? We consulted three experts and asked for their advice.

Heidi Howland, a program officer at the U.S. State Department’s Office of English Language Programs, recommends the American English app created by her employer: “There are millions of people who might not have access to technology other than their basic phones; this app serves customers that smartphone apps can’t.”

Kenneth Beare teaches English as a second language (ESL) in Portland, Oregon, and is the resident ESL expert at About.com, a site offering information on a range of subjects. His top picks are Conversation English, Travel English and English at Work: “All three have engaging storylines. They’re adapted to modern English usage, rather than academic English.”

Kelly Roell is a Tampa, Florida–based author and resident test-preparation expert at About.com. She cites Living Language, busuu and Duolingo: “Living Language and busuu get a lot of good press…and I like Duolingo’s engaging interface.”

AppsCompatibilityFeaturesLevelCost
American EnglishBasic phone, AndroidCompresses data for fast download; offers thousands of videos, books; lesson plans. Beginner, Intermediate, AdvancedFree
Conversation EnglishiPhone Dialogue-based lessons teach idiomatic English; audio, video clips; vocabulary reviews. Storyline follows friends in various real-life situations.Intermediate$2.99
Travel EnglishiPhone Dialogue-based lessons teach idiomatic English; audio, video clips; vocabulary reviews. Takes learner through deciding on a vacation to returning home.Intermediate$2.99
English at WorkiPhone Dialogue-based lessons teach idiomatic English; audio, video clips; vocabulary reviews. Teaches speech for applying for a job to first day at work.Intermediate$2.99
Living LanguageiPhone Teaches essential words/phrases and grammar; games; virtual “flash cards.”Beginner, IntermediateFree-$9.99
BusuuiPhone, Android Social-network model lets users interact with native speakers; high-quality images provide visual context for vocabulary.Beginner, Intermediate, AdvancedFree-$127
DuolinguoiPhone, Android Audio and high-quality images; bite-sized lessons build vocabulary, grammar skills; offers instruction in 21 languages.Beginner, Intermediate, AdvancedFree

More resources for improving your English are available at the U.S. Department of State’s American English website.