Features & Capabilities

DUO LINK 4 is a companion app designed to work with the DUO LINK OTG USB 3.0 Flash Drive, bringing easy file transfer, sharing, backup, and streaming to iPhone and iPad. It frees up space on iOS devices, stores photos directly on the drive, and can even charge your device while connected. You can manage files across iPhone, iPad, and DUO LINK and enjoy independent music and video playback.

Key features include automatic photo and video backups, contact backups, and seamless transfer of videos, photos, and more. The app supports common formats such as M4V/MP4/MOV video, M4A, MP3, WAV audio, JPEG/PNG/GIF images, and many documents (DOC, DOCX, PDF, PPT, XLS, HTML). PNY provides support; by downloading you agree to the End User License Agreement.

User Growth & Download Statistics

App Data
By:
PNY
Rating:
2.10
(510)
1 ratings
Version:
1.0.86 Last updated: 2023-12-14
Version code:
860959135
Creation date:
2016-05-31
Compatible devices:
Size:
123.27MB
URLs:
Privacy policy
Full description:
See detailed description
Source:
Apple Apps Store
Data ingested on:
2026-06-06
Compare stats and ranking:

Ranking

Contact the developer

Chrome-Stats does not own this Apple app. Please use these information below to contact the Apple app developer.
Developed by:
PNY
Apple Apps Store
https://apps.apple.com/us/app/duo-link-4/id1103672387

User Reviews

Users report widespread instability and compatibility problems with Duo Link 4. The app frequently crashes, struggles with USB-C devices, and can corrupt or lose transferred media. Compatibility with newer iPhones/iPads and Files app integration are common pain points; support and updates appear limited. Some positives include a working Lightning path for some devices and the app's organization features, plus the ability to offload storage to the external drive. Overall, reliability is questionable despite its intended usefulness.
Pros
  • Lightning-compatible operation on devices using Lightning (works for some users).
  • App helps organize files/media when it functions.
  • Potential to free up phone storage by moving photos/videos to the external Duo Link drive (reported by some users).
Cons
  • Frequent crashes and instability, including crashes on startup and during use.
  • Significant USB-C/newer-device compatibility issues; devices not detected or not supported.
  • Data integrity problems: photos/videos corrupted or missing after transfer.
  • Poor support and lack of ongoing updates; clunky UI and difficult workflow.
  • Limited iOS Files integration and need for internet/extra steps to transfer (not seamless).
Recent reviews
I have several PNY hardware devices which have been reliable and well designed. I bought the PNY duolink usb expecting similar results. The usb is fine but to use the usb it is all about the SOFTWARE that works with iPhone. PNY should be ashamed to have such a poor and buggy software associated with their products. Appears they outsourced the software to sell usb hardware and now have a pile of garbage the consumer is left to deal with. DO NOT BUY PNY DUOLINK USB DRIVES - you will regret it
by ma*****, 2026-05-19

This works if you have the lightning version, but if you try to use the USB-C version it doesn’t. Other companies have similar apps that work for the USB-C as well so I wish y’all would pay attention & do the same. Tech support hasn’t really been helpful other than telling me to manually move them over, but even then if I select all I can’t unless I do them in multiple small batches which is time consuming.
by An*****, 2026-03-09

Don’t even waste your money
by st*****, 2025-10-04
View all user reviews ›

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