This is why I wear practical but unfashionable trousers with side pockets on the legs, where wallet, phone and anything else bulky can be stored so that I can seat myself with reckless abandon without a high pitched scream or the sound of a glass screen cracking.
Or...ummm....the sound of a crack cracking on a glass screen perhaps?
On a related note, people of a certain age (yoof) seem to carry mobile phones (on the rare occasions that they aren't actively using them) sticking half way out of a rear pocket. This looks insecure on various levels; invitation to pickpockets, ease of losing when sitting down, whatever. I can only assume that the jeggings or whatever are so tight that it is impossible to remove the phone without the deliberate flexing of buttock muscles.