The ColorPlus kit, which comprises a USB calorimeter sensor and monitor calibration software, is designed to check and recalibrate your LCD or CRT monitor's colour settings. According to the supplied information, correcting your monitor once a month will enable you to "produce photos just like the pros". It seems a little strange, therefore, that it ships with a free copy of Adobe Photoshop Album, which is hardly the software of choice for digital image professionals.
A little recalibration might be a good thing, but unless your livelihood depends on the quality of your digital imaging, there's very little reason to spend £90 on such a device. If you really want to improve the quality of your digital photographs, get a better digital camera.