For a large share of people preparing for JFT-Basic, a phone is not the convenient option — it is the only device. It is worth knowing exactly what a phone is good at and where it quietly limits you.
What a phone does well
Spaced repetition. This is the killer application. Ten minutes of flashcards on a bus is genuinely productive, and the fragmented nature of phone time suits review perfectly. See spaced repetition for Japanese.
Listening. Headphones and twenty minutes, anywhere. The most important daily habit in your plan runs entirely on a phone.
Shadowing. Same audio, somewhere you are not self-conscious.
Reading short texts. Notices, messages, short articles — which, conveniently, is exactly what JFT-Basic reading is made of.
Looking things up. A dictionary in your pocket, with handwriting and camera input for characters you cannot type.
What a phone does badly
Full-length timed practice tests. This is the important one.
JFT-Basic is a computer-based test taken at a desk with headphones. Practising on a phone, lying down, with interruptions, rehearses a different experience. The screen size, the reading posture and the notification environment all differ from the room you will sit in.
You can and should use a phone for practice during the week. For your rehearsal sessions, find a laptop — a friend’s, a library’s, an internet café’s. Two sessions on a real computer are worth more than twenty on a phone for exam readiness. See what the screen actually does.
Sustained reading. Long passages on a small screen are harder, and at JLPT N2 and N1 where reading speed is the constraint, this matters.
Anything requiring focus for ninety minutes. Phones are interruption machines. The device that delivers your study also delivers everything competing with it.
Practical advice for phone-first study
Turn off notifications during study. Or use aeroplane mode for offline work. This single change is worth more than any app.
Download for offline use. Data is expensive, and connections in many places are unreliable. Download audio and decks in advance so a bad connection cannot break the habit.
Watch your storage and battery. A study habit that depends on an app you delete when storage runs out is fragile.
Prefer lightweight tools. Heavy apps on inexpensive Android handsets are slow enough to become a reason not to study.
Tools that work on a cheap phone
Anki is free on Android and works offline.
Our free practice test is built for this specifically: it works on a 360-pixel screen, needs no sign-up, and runs without a connection once loaded. Listening items use your phone’s own speech synthesis, so there are no audio files to download — and where a device has no Japanese voice, which is common on inexpensive handsets, the script is shown as text instead and you are told why.
That was a deliberate design decision, because most of the people taking this exam will only ever see a study site on a phone like that.
The honest summary
A phone is enough to learn Japanese. Vocabulary, listening, grammar and reading all work on one, and millions of people have done exactly that.
A phone is not enough to rehearse the exam. Find a computer for the timed full-length tests in your final month. That is a handful of sessions, and it is the difference between knowing the material and performing it.