Your requirement has got nothing to do with Ionic.
You also did not mention if this is for Android or iOS.
Anyway, you can look at the following "regular" Hybrid project: https://www.dropbox.com/s/6fgtjhzgvl6p9n0/OpenExternalApplication.zip?dl=0
It contains the needed native code to open an existing (already installed) app (Waze) in iOS.
Part of the code:
- (void)openApp:(CDVInvokedUrlCommand*)command {
NSString *wazeAppURL = @"waze://";
NSString *mapsAppURL = @"maps://";
BOOL canOpenURL = [[UIApplication sharedApplication] canOpenURL:[NSURL URLWithString:wazeAppURL]];
NSString *url = canOpenURL ? wazeAppURL : mapsAppURL;
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:url]];
NSString *responseString =
[NSString stringWithFormat:@"OK"];
CDVPluginResult *pluginResult =
[CDVPluginResult resultWithStatus:CDVCommandStatus_OK messageAsString:responseString];
[self.commandDelegate sendPluginResult:pluginResult callbackId:command.callbackId];
}