I have a son who is a first year Bais Medrash bochur who does not have nor want B”H a cell phone- he calls home on the Yeshivah pay phone- we manage to reach him when necessary on the pay phone- on the chance of there being an emergency- Chas Veshalom- we can call the office or even the Rosh Yeshivah directly-
The sakonoh far outweighs the benefit in my humble opinion-