Due to the (good) edit of the question, the answer does not seem fit 100% anymore.

No.

...which depends on what you define as a 'mobile device'. But first, the term resolution is ambiguously used which requires to answer your question in two ways.

Resolution as in pixel density

The iPad 3rd Generation has a pixel density of 264 pixels per inch (ppi). There are several other devices that provide higher pixel densities - the most well known to you is probably the iPhone 4(S).

As these belong to the mobile category, the answer is no.

iPad 3rd Gen                9.7"    2048×1536   264
iPhone/iPod touch 4,4S      3.5"    640×960     326
Rezound                     4.3"    720×1280    342 (HTC)
Touch Diamond, Touch Pro    2.8"    480×640     286 (HTC)
Touch Diamond2              3.2"    480×800     292 (HTC)
LG Optimus LTE              4.5"    720×1280    329 (LG)
LU1400                      2.8"    480×800     333 (LG)

You can get a list of more devices here.

Resolution as in total pixel count

The display of the iPad 3rd generation is referred to as QXGA (2048×1536). There are several other devices that provide higher pixel counts - e.g. the Apple iMac.

However, none of the following devices are 'mobile'. They provide higher pixel counts, but over a larger area. Hence, the answer is yes.

See this list of common resolutions for more devices. Note: Some of the resolutions stated there are only on paper - no devices implementing that resolution have been made yet according to the article.

Sony GDM-FW900 and Hewlett Packard A7217A   2304×1440    3,317,760
Dell UltraSharp U2711, Apple iMac (WQHD)    2560×1440    3,686,400
Dell Ultrasharp U3011 (WQXGA)               2560×1600    4,096,000