# QmailClient vs SiYuan

The clearest difference is review sentiment: SiYuan at 70% against QmailClient's 0%. SiYuan also leads on rating (4.0 vs 2.0) and update cadence (weekly vs every 4 months). QmailClient's advantage is in-app purchases (none vs 2). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. SiYuan sells 2 one-off in-app purchases. QmailClient asks for nothing beyond the download.

SiYuan holds the better App Store score, 4.0 against 2.0. Both are backed by a comparable volume of ratings — 6 and 29 respectively. Written reviews point the same way: 0% of QmailClient's written reviews are positive against 70% of SiYuan's.

QmailClient ships an update every 4 months, SiYuan weekly. The most recent releases landed on October 1, 2026 and October 3, 2026 respectively.

## The numbers

| Metric | QmailClient | SiYuan |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [2.0 (6 ratings)](https://appshunter.io/ios/app/qmailclient/id1087740187/reviews) | **[4.0 (29 ratings)](https://appshunter.io/ios/app/siyuan/id1583226508/reviews)** |
| Number of ratings | 6 | **29** |
| Positive reviews | 0.0% of reviews | **70.0% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 4 months | **Weekly** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 40 MB | 363 MB |
| Requires iOS | **16.0** | 17.0 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 17+ |
| Developer | [QNAP Systems, Inc.](https://appshunter.io/developer/355826923) | [Yunnan Liandi Technology Co., Ltd.](https://appshunter.io/developer/1583226510) |

## What reviewers say

### QmailClient

[App page](https://appshunter.io/ios/app/qmailclient/id1087740187)

Access and manage all your email accounts from your mobile device. Browse, compose, reply, and organize emails stored on your QNAP NAS, even offline. Attach photos directly from your phone to emails.

**Highlights:** Manage multiple email accounts, Browse emails from QNAP NAS, Attach photos to emails, Download attachments for offline reading, Read, reply, forward, and delete emails, Offline mail reading capability

**In-app purchases:** none


### SiYuan

[App page](https://appshunter.io/ios/app/siyuan/id1583226508)

A privacy-focused personal knowledge management system that allows offline use and encrypted data synchronization. It combines blocks, outlines, and bidirectional links to help users organize and refine their thoughts.

**Highlights:** Privacy-first design, Offline data storage, End-to-end encrypted sync, Block-based organization, Outline structuring, Bidirectional linking

**Features:** Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| PRO Features | $79.99 | one-time |
| Subscription | $188.99 | one-time |


## Frequently asked questions

### Is QmailClient free?

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

### Is SiYuan free?

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

### Which has better reviews, QmailClient or SiYuan?

SiYuan is rated higher. QmailClient averages 2.0 out of 5 from 6 ratings, while SiYuan averages 4.0 from 29 ratings.

### Do QmailClient or SiYuan have ads?

Neither QmailClient nor SiYuan shows ads.

### Which is updated more often, QmailClient or SiYuan?

QmailClient ships an update every 4 months, and SiYuan weekly. Most recently, QmailClient was updated on October 1, 2026 and SiYuan on October 3, 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.*