Can Canadians trade with APEX?

Yes you can. You cannot purchase a LIVE account with Tradovate. However, you can use their services through APEX accounts. 

To use NinjaTrader with your Tradovate or Rithmic account, please follow the setup instructions for NinjaTrader closely!

https://support.apextraderfunding.com/hc/en-us/articles/13631853249691-Setup-and-Connection-Guide-for-NinjaTrader-Tradovate-and-Rithmic 

If you are having trouble downloading Ninjatrader 8.1.1.7 from Canada, please try the link below:

Download Ninjatrader 8.1.1.7 from Apex