I think that’s irresponsible; what if one week the doctors are all away? Anyhow, the point wasn’t your shul, the point was shul with a jammer. It doesn’t have to be unsafe as long as there’s an accessible landline, as the OP said.
Yes, the siddur app was completely a side point, but as an aside on the side point, some siddur apps will insert as necessary according to the day and season, e.g. Ya’aleh V’yavo, V’sein B’rachah, and that might not work if there’s a jammer.