I had the exact same error as you,
the problem for me was inside ionic.project file
It was:
{
"name": "myApp",
"app_id": ""
"watchPatterns": [
"www/js/*",
"!www/css/**/*"
]
}
There was a comma missing after app_id.
{
"name": "myApp",
"app_id": "",
"watchPatterns": [
"www/js/*",
"!www/css/**/*"
]
}
Cheers