# Depth vs Smart Diary

The clearest difference is price: Smart Diary at Free against Depth's $0.99. Smart Diary also leads on rating (4.8 vs 1.0) and update cadence (every 2 months vs every 21 months). Depth's advantage is in-app purchases (none vs 1). On ads, device support and iOS requirement there is nothing between them.

Smart Diary is free to download; Depth costs $0.99 up front. Smart Diary sells 1 one-off in-app purchase. Depth asks for nothing beyond the download.

Smart Diary holds the better App Store score, 4.8 against 1.0. That said, the two scores are not equally well evidenced: Smart Diary has 42 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 50% of Depth's written reviews are positive against 66% of Smart Diary's.

Depth ships an update every 21 months, Smart Diary every 2 months. The most recent releases landed on August 22, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Depth | Smart Diary |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | [1.0 (1 ratings)](https://appshunter.io/ios/app/depth/id336473396/reviews) | **[4.8 (42 ratings)](https://appshunter.io/ios/app/smart-diary-student-planner/id1063078386/reviews)** |
| Number of ratings | 1 | **42** |
| Positive reviews | 50.0% of reviews | **65.9% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 21 months | **Every 2 months** |
| Monetization | Paid | **Free with in-app purchases** |
| Size | 73 MB | 23 MB |
| Requires iOS | **11.0** | 12.0 |
| Devices | iPhone, iPad, iPod | **iPhone, iPad, iPod, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [Pietro Massimino](https://appshunter.io/developer/332379844) | [Matteo D'Ignazio](https://appshunter.io/developer/634863524) |

## What reviewers say

### Depth

[App page](https://appshunter.io/ios/app/depth/id336473396)

Measure the depth of wells, cliffs, and other vertical drops by dropping an object and listening for the impact. It also calculates the speed of a falling object in real-time.

**Highlights:** Measure well and cliff depths, Calculate freefall speed, Real-time drop analysis, Uses sound for measurement

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### Smart Diary

[App page](https://appshunter.io/ios/app/smart-diary-student-planner/id1063078386)

This student planner helps organize your academic life by tracking homework, tests, and absences. It includes tools for time management, grade tracking, and setting academic goals. Customize your experience with themes and access advanced features through an in-app purchase.

**Highlights:** Add homework, tests, and notes, Manage absences and count by type, Time management organizer, Track and manage grades, Set academic goals, Customizable timetable, Notes with text formatting

**Features:** Apple Watch app, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium version | $2.99 | one-time |


## Frequently asked questions

### Is Depth free?

Depth costs $0.99, with no in-app purchases.

### Is Smart Diary free?

Smart Diary is free to download, with in-app purchases available.

### Which has better reviews, Depth or Smart Diary?

Smart Diary is rated higher. Depth averages 1.0 out of 5 from 1 ratings, while Smart Diary averages 4.8 from 42 ratings.

### Do Depth or Smart Diary have ads?

Neither Depth nor Smart Diary shows ads.

### Which is updated more often, Depth or Smart Diary?

Depth ships an update every 21 months, and Smart Diary every 2 months. Most recently, Depth was updated on August 22, 2026 and Smart Diary on October 24, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*