use of automobiles on Shabbat as a violation of multiple categories, including lighting a fire, extinguishing a fire, and transferring between domains (category 39). However, the Conservative movement's Committee on Jewish Law and Standards permits driving to a synagogue on Shabbat, as an emergency measure, on the grounds that if Jews lost contact with synagogue life they would become lost to the Jewish people. A halakhically authorized Shabbat mode added to a power-operated mobility scooter may be used on the observance of Shabbat for those with walking limitations, often referred to as a Shabbat scooter. It is intended only for individuals whose limited mobility is dependent on a scooter or automobile consistently throughout the week. Modifications Seemingly "forbidden" acts may be performed by modifying technology such that no law is actually violated. In Sabbath mode, a "Sabbath elevator" will stop automatically at every floor, allowing people to step on and off without anyone having to press any buttons, which would normally be needed to work. (Dynamic braking is also disabled if it is normally used, i.e., shunting energy collected from downward travel, and thus the gravitational potential energy of passengers, into a resistor network.) However, many rabbinical authorities consider the use of such elevators by those who are otherwise capable as a violation of Shabbat, with such workarounds being for the benefit of the frail and handicapped and not being in the spirit of the day. Many observant Jews avoid the prohibition of carrying by use of an eruv. Others make their keys into a tie bar, part of a belt buckle, or a brooch, because a legitimate article of clothing or jewelry may be worn rather than carried. An elastic band with clips on both ends, and with keys placed between them as integral links, may be considered a belt. Shabbat lamps have been developed to allow a light in a room to be turned on or off at will while the electricity remains on. A special mechanism blocks out the light when the off position is desired without violating Shabbat. The Shabbos App is a proposed Android app claimed by its creators to enable Orthodox Jews, and all Jewish Sabbath-observers, to use a smartphone to text on the Jewish Sabbath. It has met with resistance from some authorities. Permissions If a human life is in danger (pikuach nefesh), then a Jew is not only allowed, but required, to