Unfortunately that looks to be the case. I had hoped they'd rolled their own push server implementation in the linked source (https://github.com/EFForg/pushserver), but it's just a wrapper around the GCM and APNS services.
It's disappointing, because both Android and iOS have support for periodically retrieving data without using the proprietary push services. It's not like the EFF is going to be delivering messages that have a 'real-time' requirement and therefore require a persistent connection (as opposed to say, Gmail/Hangouts).
It's disappointing, because both Android and iOS have support for periodically retrieving data without using the proprietary push services. It's not like the EFF is going to be delivering messages that have a 'real-time' requirement and therefore require a persistent connection (as opposed to say, Gmail/Hangouts).