how can I get IMEI in IOS with ionic framework ?
This will not be possible sadly.
Apple stopped access to these details in iOS7 I believe.
If I don’t say a mistake, it was never possible to get the IMEI of an iPhone by iOS APIs. Until iOS 7, you could access to the UUID which is a unique device identifier but they change it to another identifier and you can have access to it only if you have advertising in your app.