# SumDU vs hYYa Encrypted Notes & Sync

The clearest difference is in-app purchases: SumDU at none against hYYa Encrypted Notes & Sync's 1. SumDU also leads on iOS requirement (12.1 vs 26.0). hYYa Encrypted Notes & Sync's advantage is update cadence (every 4 days vs every 8 months). On price, ads and device support there is nothing between them.

Both are free to download. hYYa Encrypted Notes & Sync sells 1 one-off in-app purchase. SumDU asks for nothing beyond the download.

SumDU ships an update every 8 months, hYYa Encrypted Notes & Sync every 4 days. The most recent releases landed on November 1, 2026 and November 8, 2026 respectively.

## The numbers

| Metric | SumDU | hYYa Encrypted Notes & Sync |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/sumdu/id698235283/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 8 months | **Every 4 days** |
| Monetization | Free | — |
| Size | 14 MB | 7 MB |
| Requires iOS | **12.1** | 26.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, Mac |
| Age rating | 4+ | 4+ |
| Developer | [App Dev Academy Ltd.](https://appshunter.io/developer/1281918813) | [Hassaan Abdeen](https://appshunter.io/developer/1866789892) |

## What reviewers say

### SumDU

[App page](https://appshunter.io/ios/app/sumdu/id698235283)

Access your university schedule, including classes, professors, and rooms, all in one convenient app. Download your schedule for offline use and sync it with your device's calendar to avoid missing appointments.

**Highlights:** University schedule access, Professor and auditorium schedules, Offline schedule download, Calendar integration, Schedule for all groups

**In-app purchases:** none


### hYYa Encrypted Notes & Sync

[App page](https://appshunter.io/ios/app/hyya-encrypted-notes-and-sync/id6792328099)

**Features:** iPhone Duo support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| hYYa Encrypted Notes Pro | $19.99 | one-time |


## Frequently asked questions

### Is SumDU free?

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

### Is hYYa Encrypted Notes & Sync free?

hYYa Encrypted Notes & Sync is free to download, with in-app purchases available.

### Do SumDU or hYYa Encrypted Notes & Sync have ads?

Neither SumDU nor hYYa Encrypted Notes & Sync shows ads.

### Which is updated more often, SumDU or hYYa Encrypted Notes & Sync?

SumDU ships an update every 8 months, and hYYa Encrypted Notes & Sync every 4 days. Most recently, SumDU was updated on November 1, 2026 and hYYa Encrypted Notes & Sync on November 8, 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.*