DUO LINK 4 vs Feedstack
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
DUO LINK 4
Manage and transfer files between your iOS device and a USB flash drive. Free up storage, back up data, and even charge your device. Supports a wide range of file formats for seamless integration.
- Free up iPhone/iPad space
- Charge iOS devices
- Back up contacts
- Transfer photos and videos
- Store photos directly
- Manage files
- Music and video playback
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PNY DUO LINK 4 app, designed to work with DUO LINK OTG USB 3.0 Flash Drive brings you the ability to do more when it comes to file transfer, saving, sharing, accessing and streaming. Simply connect the DUO LINK OTG USB 3.0 Flash Drive to your iPhone and iPad and start syncing, transferring, sharing files, photos, videos and more with ease. DUO LINK OTG USB 3.0 is a flash drive designed for iPhone and iPad that enables you to free up space on your iOS device, save and protrect your contents into DUO LINK and even transfer then to your computer. DUO LINK OTG USB 3.0 also provides the ability for you to charge your iPhone and iPad. Features and Benefits: - Free up space on your iPhone or iPad. - Charge your iOS device. - Back-up your contacts. - Transfer and share your videos, photos and more. - Store photos directly into DUO LINK and save space on your iPhone or iPad. - Manage files on your iPhone, iPad and on DUO LINK. - Supports independent music and video playback. - Automatically back up your photos and videos so that you don't have to. Support: Please visit PNY Support at www.pny.com/support/technical-support Supported file formats: - video: M4V/MP4/MOV - Audio: M4A, CAF, AIFF, ASF, AAC, mp3, wav - Picture: TIFF, JPEG,JPG,PNG,GIF,BMP - Document: DOC, DOCX, PAGES, RTF, TXT , PPT, PPTX, PDF, XLS, XLSX, NUMBERS, KEY, HTML PNY takes no responsibility or liability with respect to the download or usage of DUO-LINK 4 app. By downloading this app you agree to the end user license agreement from PNY, also available at http://www.pny.com/File%20Library/Unassigned/PNY--On-the-Go-End-User-License-Agreement.pdf .
Feedstack
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You save videos, posts and articles you mean to come back to, and then never open them again. Feedstack fixes that. Paste any link and it becomes a daily habit with a reminder and a streak counter. Pick the time, and Feedstack nudges you every day until it sticks. Paste a link from YouTube, TikTok, X, Instagram, Reddit, Spotify or any website. Each habit keeps the original link, so you can go straight to what you saved. Choose a daily reminder time for every habit. Your day appears as a timeline, so you see what is planned and when. Watch your streak grow. A counter and a calendar show every day you completed, and badges mark milestones. Add friends as streak buddies and take on monthly challenges together. Sort habits into categories like health, exercise and learning, and get suggestions for similar habits. No account needed to start. Your habits and streaks stay on your device. Feedstack Pro unlocks more. Subscriptions and a one-time lifetime purchase are available in the app. No account. No ads. No data collected. Everything stays on your device. Terms of Use: https://apple.com/legal/internet-services/itunes/dev/stdeula/
Screenshots
Verdict
The clearest difference is in-app purchases: DUO LINK 4 at none against Feedstack's 3. DUO LINK 4 also leads on iOS requirement (11.0 vs 15.1). On price, update cadence, ads and device support 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. Feedstack sells 3 in-app purchases, starting at $2.99 per month. DUO LINK 4 asks for nothing beyond the download.
DUO LINK 4 ships an update every 2 months, Feedstack every 6 weeks. The most recent releases landed on November 2, 2026 and October 28, 2026 respectively.
| Parameter | DUO LINK 4 | Feedstack |
|---|---|---|
| Price | Free | Free |
| Rating | 2.1 (513 ratings) — better | — |
| Positive reviews | 19.8% of reviews | — |
| Number of ratings | 513 — better | — |
| Update frequency | Every 2 months | Every 6 weeks — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Free | — |
| Devices | iPhone, iPad, iPod — better | iPhone, iPod |
| Requires iOS | 11.0 — better | 15.1 |
| Further details — not scored | ||
| Size | 123 MB | 43 MB |
| Age rating | 4+ | 4+ |
| Developer | PNY | Smira Shah |
Bugs and requests
DUO LINK 4
Reported bugs
3 issues- App fails to detect connected device
- Transferred files not visible or accessible
- Inconsistent behavior when renaming folders
Requested features
4 requests- Add 'select all' option for photos/files
- Support for more file formats
- Improve iPad app experience
- Integrate with native Files app
Feedstack
Not enough reviews yet to summarise bugs or requests.
In-app purchases
DUO LINK 4
No in-app purchases
Feedstack
- FeedStack Pro Monthly$2.991 Month
- FeedStack Pro Annually$17.991 Year
- FeedStack Lifetime$24.99
