Q. My third question is:(See questions 2740-41 above): If that is OK, could they then accept upon themselves some restrictions. For example, it is popular today for people to do a "media fast" where they don't use their phones or computers. Would undertaking that kind of voluntary abstinence from technology in addition to honoring the Shabbat be OK?
A. See answer above regarding the observance of Shabbos for a prospective ger.
Horav Shlomo Miller's usual opinion is that "media fasts" should be encouraged as much as possible for all and at all times.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit'a