ists of two sheets of coated material separated by microdots, each with horizontal and vertical lines. When the sheets are pressed together, the exact location of the touch is determined by the lines of the two sheets coming in contact with one another. Because this technology is non-electric, it can be used with a stylus as well as a hand touch. This is less costly than capacitive technology. Resistive technology is not as satisfactory for hand input, because users need to press down on the display with greater force to elicit a response. Mobile and Wi-Fi Networks Battery Life Because mobile devices are multifunctional, portable, and easier to use, people are more dependent on them for their voice and text communications as well as social net- working, music, and increasingly, video, as well. They also use these devices on Wi-Fi networks and for video conferences. Data applications require more power from the device. Bandwidth-heavy applica- tions such as Internet access, video, and e-mail drain batteries more quickly than voice calls. This is because voice requires fewer bits to transmit than does data. In addition, large color displays drain batteries more quickly than the less-sophisticated screens on earlier devices. Thus, as people become increasingly dependent on mobile devices for more functions, it is important to find ways to extend battery life. Currently, mobile devices, including smartphones and tablet computers, use lith- ium-ion batteries. Although there is ongoing research into improving battery life, there are no breakthroughs expected in the near future. But, this does not mean that manu- facturers are not looking at other ways to provide longer battery use. A current focus is on ways to design mobile handsets that use power more effi- ciently. One such technology, developed by QuickLogic, extinguishes screen back- lighting when it is not required. The QuickLogic technology senses ambient lighting to determine when backlighting is needed. It maintains color by creating brighter color pixels SO t