# Trigonometry Identities — Trig formulas & AI tutor

> Trig formulas & AI tutor (iPhone/iPad app by Andres Florez.)

- Source: https://appshunter.io/ios/app/trigonometry-identities/id1565030240 (this page in markdown: same URL + `.md`)
- Developer: [Andres Florez](https://appshunter.io/developer/1565030242)
- Category: Education, Reference
- Price: Free with in-app purchases (on sale, was $0.99)
- Age rating: 4+
- Requires: iOS 15.0 · 28 MB
- Languages: English
- Released: 2021-04-29
- Data updated: 2026-11-11

## What is Trigonometry Identities?

Trigonometry, clear and in your pocket.

Trigonometry Identities brings together every formula you need for high school, college prep and university (calculus, physics, engineering), with interactive tools that help you actually understand them.

▸ EVERY IDENTITY
• Pythagorean and reciprocal
• Sum and difference of angles
• Complementary, supplementary and opposite angles
• Double, triple and half angle
• Power reduction
• Sum-to-product and product-to-sum
• Law of sines and law of cosines
Crisp formulas, with search and favorites. Long-press any formula to copy it as LaTeX.

▸ INTERACTIVE UNIT CIRCLE
Drag the angle and watch sine, cosine and tangent update live. It snaps to the special angles (30°, 45°, 60°…) and shows the exact value, like √3/2, plus the angle in radians.

▸ SOLVE TRIANGLES STEP BY STEP
Enter any 3 values and get the sides, angles, area and perimeter, with the working and a drawing to scale. It handles the ambiguous case too: when two triangles are possible, it shows both.

▸ IDENTITY LAB
Is sin 2x equal to 2·sin x·cos x? Type both expressions: the app tells you whether they are an identity and plots both graphs so you can see why.

▸ DARK MODE, WORKS OFFLINE
No internet needed. In English and Spanish (follows your phone's language).

Great for high school, SAT/ACT prep, calculus and physics students.
No ads. No sign-up.

▸ AI TUTOR
• Tap the AI button on any formula for a free step-by-step explanation
• In the Lab, ask for a step-by-step proof (3 free per day)
• Optional AI tutor subscription (monthly or yearly) for unlimited proofs

Pro (one-time purchase) unlocks unlimited practice, timed exam mode and the printable PDF formula sheet.

The AI tutor subscription renews automatically at the same price unless cancelled at least 24 hours before the end of the current period. Manage or cancel it in your App Store account settings.
Terms of Use (EULA): https://27industries.com.co/terminos/
Privacy Policy: https://27industries.com.co/privacidad/identidades/

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| AI tutor yearly | $14.99 | per year |
| AI tutor monthly | $2.99 | per month |

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Pro | $3.99 | one-time |


## Is Trigonometry Identities safe?

Not enough ratings yet to assess Trigonometry Identities.

## Is Trigonometry Identities legit?

Trigonometry Identities appears to be a legitimate app. The AppsHunter Legitimacy Score for Trigonometry Identities is 90 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 2 releases)

### 3.4.1 — 2026-11-09

All-new app for iPhone and iPad: in English and Spanish, interactive tools, practice, exam mode and the new AI tutor.

### 1.0.1 — 2021-04-29

No release notes.

## More apps by Andres Florez

- [Derivatives Integrals Formulas](https://appshunter.io/ios/app/derivatives-integrals-formulas/id1566450149)
- [Fénix](https://appshunter.io/ios/app/fenix/id6761237956)
- [321 YAPP](https://appshunter.io/ios/app/321-yapp/id6765719778)

All apps by Andres Florez: https://appshunter.io/developer/1565030242

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-11-11.*