Apps, Apps and More Apps
The front-end is a visual treat, but digging deeper will reveal Control Panel menus that most existing Qnap users will be familiar with. Various settings - such as creating new users - are handled via near-identical wizards, however the interface on the whole doesn't feel quite as nippy and we did notice a few minor rendering issues in Internet Explorer, where icons weren't always in perfect alignment.
QTS 3.x may have been lacking in effects, but its utilitarian approach made it fast and responsive, whereas QTS 4.0's various transitions make it feel a touch slower. It's tough to compare the two directly - we confess we had QTS 3.8 running on a higher-end TS-469 Pro - but nonetheless, QTS 4.0 on the TS-421 didn't feel quite as responsive as we'd like.
[Update] Qnap has confirmed that QTS 4.0 performance has been improved in the latest available release.
In keeping with the recent trend, Qnap has also introduced a dedicated App Center to QTS 4.0. The majority of available apps are developed by Qnap itself, and all are available at no extra fee. Being able to add and remove apps with ease makes NAS customisation that little bit easier, and Qnap has repackaged many of its core solutions as independent apps, making the system more modular in nature. Instead of being bombarded with Download Station, DJ Station, Music Station, Photo Station, Surveillance Station (...you get the point), the user can simply choose which apps to install.
Unsurprisingly, it's in these very apps that QTS 4.0 contains the most upgrades. Entertainment apps such as Music Station and Photo Station have been given a unified interface, with the ability to preview photos, music and videos using a built-in media player, and various social networks are given tighter integration, allowing users to share photos or other multimedia content direct to Facebook or Twitter, among others. Perhaps one of the most useful apps is Qsync, which despite being in beta form, works well as a cross-platform, multi-device file synchronisation service.
Managing and accessing multimedia content from anywhere is one of the TS-421's greatest strengths. The NAS offers support for iTunes Server, Squeezebox, DLNA, Apple AirPlay, and a range of mobile apps designed for iOS and Android. Sorry, no love for Windows Phone as yet.
On the whole, Qnap has taken the required steps and revamped its NAS operating system, yet QTS 4.0 delivers mixed results. It's undoubtedly easy on the eye, and the App Center has plenty of potential, however the operating system still feels rough around the edges and arguably isn't as polished as rival solutions. We've reached out to Qnap on when QTS 4.0 will be made available to other NAS products, but we've had no response and suspect it may be another month or two to allow for further refinement.
[Update] Qnap has confirmed that QTS 4.0 will be released for TS-x10, x12, x19, x39, x59, x69, 509, 809 and SS-x39 in June 2013.