# Ai Study vs Navien Sphere for Sleep

The clearest difference is review sentiment: Navien Sphere for Sleep at 50% against Ai Study's 0%. Ai Study's advantage is iOS requirement (10.0 vs 15.0). On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Ai Study ships an update every 2 months, Navien Sphere for Sleep every 5 weeks. The most recent releases landed on October 22, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Ai Study | Navien Sphere for Sleep |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[3.3 (3 ratings)](https://appshunter.io/ios/app/navien-sphere-for-sleep/id6762114608/reviews)** |
| Number of ratings | — | **3** |
| Positive reviews | 0.0% of reviews | **50.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 5 weeks** |
| Monetization | Free | Free |
| Size | 5 MB | 255 MB |
| Requires iOS | **10.0** | 15.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Vson Technology Co., Ltd](https://appshunter.io/developer/938010223) | [KYUNGDONG NAVIEN CO.,LTD](https://appshunter.io/developer/456445012) |

## What reviewers say

### Ai Study

[App page](https://appshunter.io/ios/app/ai-study/id1631661998)

This tool helps children practice mental arithmetic with smart tracking of progress and performance. It categorizes correct and incorrect answers, monitors time spent, and provides daily topic statistics. A smart alarm clock feature is also included for reminders.

**Highlights:** Summarizes topic records, Classifies correct/wrong answers, Tracks time and correct rate, Monitors daily topics, Smart alarm clock reminder

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

**In-app purchases:** none


### Navien Sphere for Sleep

[App page](https://appshunter.io/ios/app/navien-sphere-for-sleep/id6762114608)

Control your smart sleep device remotely, manage its settings, and personalize your sleep environment. Features include seasonal temperature adjustments, automatic sleep pattern adaptation, and dual-zone temperature control for ultimate comfort.

**Highlights:** Remote device control, Personalized sleep management, Seasonal temperature modes, Automatic temperature adjustment, Dual-zone temperature control, Customizable schedules

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

**In-app purchases:** none


## Frequently asked questions

### Is Ai Study free?

Ai Study is free to download, with no in-app purchases.

### Is Navien Sphere for Sleep free?

Navien Sphere for Sleep is free to download, with no in-app purchases.

### Do Ai Study or Navien Sphere for Sleep have ads?

Neither Ai Study nor Navien Sphere for Sleep shows ads.

### Which is updated more often, Ai Study or Navien Sphere for Sleep?

Ai Study ships an update every 2 months, and Navien Sphere for Sleep every 5 weeks. Most recently, Ai Study was updated on October 22, 2026 and Navien Sphere for Sleep 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.*