I believe it only uses push to receive a notification that a new message is on the server, when the app is in the background. Then Signal polls the server and retrieves the message(s). I've broken Play Services (including Push) on phones with Signal installed, and I could still receive messages, including in real time when the app was in the foreground and the device screen was on.
I don't know if Play Services are needed for installing, but they're not strictly necessary for functioning. Although I will say, opening the app and receiving a bunch of messages from hours ago from people who are trying to contact you is not exactly the best of experiences, so in that respect, push is rather important.
________________________________________
From: whispersystems-***@lists.riseup.net [whispersystems-***@lists.riseup.net] on behalf of Alexis Wattel [***@gmail.com]
Sent: Friday, January 01, 2016 9:07
To: ***@lists.riseup.net
Cc: B
Subject: Re: [whispersystems] Signal on a Blackberry
I think that Signal uses Google's Push service, which won't work on BlackBerry.
Message d'origine
De: B
Envoyé: jeudi 31 décembre 2015 20:20
À: ***@lists.riseup.net
Répondre à: B
Objet: Re: [whispersystems] Signal on a Blackberry
it just does not install eventhough it says it will sometime soon...
Post by Sam Lanningwhat's preventing you from getting it from the play store? does it say it
isn't compatible, or you can't find it? Or something else?
Sam.
Post by InfoAhoy y'all,
I'm looking for a way to install signal on my Blackberry.
Does anyone know how to do that?
I can't get it from the GooglePlay-store...
Cheerz