Apex Legends has been suffering from crashes on all three platforms - PC, PlayStation 4 and Xbox One. Crashes vary in causes and error display, but some solutions appeared for the most common one on PlayStation 4 - the infamous CE-34878-0.
Several players have reported that their woes named CE-34878-0 disappeared into thin air as soon as they got rid of a certain VoIP feature in Apex Legends' settings. Simply going to Audio settings and turning "Convert Incoming Voice to Chat Text" reportedly fixed the crashing issue for many players. Bear in mind that CE-34878-0 started appearing for them about the same time they turned VoIP on, so this could be only a smaller batch of players who got lucky with the fix.
AltChar's own Heavy Messing wasn't so lucky, as this particular fix didn't yield results and his PS4 version of Apex Legends crashed soon after turning the option off. Another suggestion comming from Apex Legends community is to turn off the boost mode, in case you are playing on PS4 Pro.
Considering that Apex Legends is pretty much plagued by crashes across all three platforms at this point, it's hard to pin all the blame on one or two features, especially since boost mode is native to PS4 Pro. It is obvious that many issues originate on Respawn Entertainment's end and players are calling for fixes.
The company didn't officially state whether fixes are underway, and neither did they explicitly admit that these error are an issue on their end, but considering that Apex Legends blew up in popularity, it is quite possible that Respawn didn't predict this server load. No one really saw one million players coming in the first eight hours and even fewer could anticipate the 25 million players milestone to be broken in just a week.
Vince Zampella announced that concurrent player count broke through two million already. If the crashes do indeed originate with heavy server load, Respawn are not to blame just yet - no one really prepares for such a player base burst.
On the other hand, if you happen to be a PC player with an AMD Phenom or an older Intel CPU, server load definitely doesn't prevent you from playing Apex Legends, as the game will not run on these processors.