Maths Apps That Actually Work: A Teacher's Tested Review of 12 Popular Options

I tested these apps systematically because I was tired of recommending things based on how polished the interface was. Good design doesn't equal effective learning, and several of the most beautiful maths apps I've used have done remarkably little for students who struggle with the underlying concepts.

Here's my honest assessment of 12 apps that HK students are using.

The apps that genuinely support learning

Khan Academy (Free — iOS/Android/Web)

Still the benchmark. The explanations are patient, the progression is logical, and the exercise system adapts to where a student is struggling. For primary and lower secondary maths, the alignment with the HKDSE curriculum is imperfect but workable — the core concepts transfer even if the terminology occasionally differs. Khan Academy's recent AI tutor feature, Khanmigo, is among the best implementations of AI as a learning guide I've seen: it prompts students to think rather than just giving answers.

Verdict: Use it. Ten minutes a day on Khan Academy, focused on the current topic in school, is the single most consistent homework supplement I recommend.

Photomath (Free with paid tier — iOS/Android)

I've changed my view on this one over three years. Originally I disliked it because it gives complete solutions. Now that I've seen how students actually use it, I'm more positive. The step-by-step explanations for many topics are genuinely clear. For a student stuck at 10pm with nobody to ask, working through a Photomath explanation of factorisation or quadratic equations can unblock them.

The risk is unchanged: it's easy to screenshot solutions without engaging with them. The test is always: can the student do a similar problem the next day without the app?

Verdict: Useful but requires discipline. Not for building new concepts — for checking understanding and unblocking confusion.

Geogebra (Free — Web/iOS/Android)

For geometry and graphing functions, Geogebra is exceptional. The visualisation of geometric relationships — angles, transformations, circle theorems — is beautifully done and the interactive elements build intuition in ways static diagrams can't. For S1-S3 students working with coordinate geometry or S4-S5 students dealing with functions and graphs, Geogebra deserves more use than it gets.

Verdict: Excellent for geometry and functions. Currently underused in HK classrooms.

Desmos (Free — Web/iOS/Android)

The graphing calculator that should replace expensive physical calculators for secondary students doing functions. Immediate visual feedback on how changing a parameter shifts a graph is far more instructive than reading a description. For S4-S6 students doing DSE Maths Core or Extended, Desmos is a legitimate study tool for developing graphical intuition.

Verdict: Essential for S4-S6 functions work.

Quizlet (Free with paid tier — iOS/Android/Web)

Not maths-specific, but worth including for formula and definition memorisation. Custom flashcard sets for DSE maths formulae — circle theorems, trig identities, statistical formulas — can be studied during commute time. The spaced repetition algorithm actually works. The game modes make it more engaging than staring at a formula sheet.

Verdict: Good for memorisation within a broader study strategy.

The apps that are fine but overrated

Prodigy (Free — Web)

An RPG-style maths game aimed at primary students. The gamification is well-designed and children often enjoy it. The maths itself is narrow — primarily arithmetic and some number sense — and the subscription tier gates a lot of content. For a child who refuses to do any maths practice, it's better than nothing. For a child who needs to develop genuine mathematical reasoning, it's insufficient.

Verdict: Better than screen time alone. Not a substitute for real maths practice.

Mathletics (Paid subscription)

Used by some HK primary schools as a homework platform. The questions are decent, the reporting for teachers is good, and the multi-player features create some motivation. The content alignment to HK curriculum is better than most US-based apps. The price is significant and the learning depth isn't substantially better than Khan Academy.

Verdict: Fine if the school is already using it. Not worth purchasing independently.

DragonBox (Paid — iOS/Android)

An innovative app for introducing algebra concepts through puzzle-solving. The underlying pedagogical approach — isolating unknowns before introducing algebraic notation — is creative and has research support. In practice, the transfer to formal algebraic notation is often incomplete; children enjoy the game but struggle when presented with traditional equations.

Verdict: Creative introduction. Insufficient as the sole approach to algebra.

The apps I'd avoid or approach with caution

Any app that does homework directly without explanation. There are several apps (some quite prominent) that will solve a homework problem when you photograph it, without providing explanation or walkthrough. The grade appears without the learning. These are not learning tools.

Apps with aggressive reward systems designed to maximise engagement. The distinction between "motivating to learn" and "addictive to use" is real. An app that rewards streaks and creates anxiety about breaking them is prioritising engagement metrics over learning outcomes. Check whether your child is stressed about losing their streak versus excited about what they learned.

Free apps with heavy advertising. Not an educational issue per se, but advertisements in a learning environment are distracting and some apps target children with inappropriate commercial content.

A simple framework for evaluating any maths app

Ask three questions. Does it explain the concept or just give the answer? Can my child do a similar problem after using it? Would they use it if it didn't have game elements or rewards?

The first question is about depth. The second is about genuine learning versus performance. The third reveals whether the mathematics or the gamification is doing the motivating.

Good apps pass all three. Most apps pass one.