The Introduction of Microsoft Pocket PC 2000/2002 has seen a standardisation of the operating systems used by the majority of PDA manufacturers. This, coupled with the recent price reductions associated with these devices, has led to a rapid increase in the sales of such units; their use is now common in industrial, commercial and domestic applications throughout the world. This paper describes the results of a programme to develop a thermal imager that will interface directly to all of these units so as to take advantage of the existing and future installed base of such devices. The imager currently interfaces with virtually any Pocket PC which provides the necessary processing, display and storage capability; as an alternative, the output of the unit can be visualised and processed in real time using a PC or laptop computer. In future, the open architecture employed by this imager will allow it to support all mobile computing devices, including phones and PDAs. The imager has been designed for one-handed or two-handed operation so that it may be pointed at awkward angles or used in confined spaces; this flexibility of use coupled with the extensive feature range and exceedingly low-cost of the imager, is extending the marketplace for thermal imaging from military and professional, through industrial to the commercial and domestic marketplaces.