The wide verity of devices on offer and the adjustments applied by the manufactures to the operating systems of individual devices presents great difficulties in the creation of a fully compatible solution.

The inherent properties in Mobile 5 and Mobile 6 operating systems, the successful and less successful ones and especially those which relate to the phone and SMS interface are integrated in the device’s hardware – software architecture and any attempt by an application to “tame” them reduces the compatibility and reliability of that application especially in devices that were not specifically tested.

This issues is even more crucial as the operating system is embedded in the device by the manufacturer, AFTER adjustments have been made, adjustments which differ from one device model to another and even more so between different manufacturers.

The approach used in the development of O3touch was to avoid manipulating the inherent functionality of the device as supplied by the manufacturer, but rather to look for ways to coexist with the different function that function integrally as part of the operating system and the default dialer even at the cost of avoiding more simple solutions to some issues.

As an example we could mention the issue of physical device button (red and green) operation the access to which by the operating system differs from one device to another, or the functionality and possibility of changing the function of the “X” and “OK” buttons (located at the top right hand corner) and arising from that the issues of software closure and “operating in background” mode.

For these reasons software compatibility is not required for framework 3.5 rather for the up to date version 2 in order to minimize the requirements ahead and during the installation process.