QmailClient vs SiYuan
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
QmailClient
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.
- 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
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Manage all of your email accounts in the same place ! Connect your email accounts on your QNAP NAS with your iOS mobile devices to get started. Prerequisites: - iOS 16 or above - QNAP NAS running firmware version 4.3.3 or above Features: - Browse the email accounts on the Turbo NAS anytime, anywhere. - Support to attach photo from your mobile when compose mail. - Download your attachments to mobile devices for offline reading. - Easy management: Read, reply, replay, forward, move, flag, mark or delete mails on the Turbo NAS, all via your mobile device. No computer required. - Offline mail reading: QmailClient cache your mail from the Turbo NAS to mobile devices for offline reading.
SiYuan
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.
- Privacy-first design
- Offline data storage
- End-to-end encrypted sync
- Block-based organization
- Outline structuring
- Bidirectional linking
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SiYuan is a privacy-first personal knowledge management system that supports complete offline use, as well as end-to-end encrypted data sync. Fuse blocks, outlines, and bidirectional links to refactor your thinking.
Screenshots
Verdict
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.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
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.
| Parameter | QmailClient | SiYuan |
|---|---|---|
| Price | Free | Free |
| Rating | 2.0 (6 ratings) | 4.0 (29 ratings) — better |
| Positive reviews | 0.0% of reviews | 70.0% of reviews — better |
| Number of ratings | 6 | 29 — better |
| Update frequency | Every 4 months | Weekly — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Free — better | Free with in-app purchases |
| Devices | iPhone, iPad | iPhone, iPad |
| Requires iOS | 16.0 — better | 17.0 |
| Further details — not scored | ||
| Size | 40 MB | 363 MB |
| Age rating | 4+ | 17+ |
| Developer | QNAP Systems, Inc. | Yunnan Liandi Technology Co., Ltd. |
Customer experience
QmailClient
SiYuan
In-app purchases
QmailClient
No in-app purchases
SiYuan
- PRO Features$79.99
- Subscription$188.99
