Where can I find WhatsApp themes for iOS devices?

WhatsApp provides just the default theme, no more themes are available in official WhatsApp. If you need more themes and want to customize your app look then download the modified version of WhatsApp. This modded version provides various themes you can select one of them and use it in this version.

Is GBWhatsApp for iOS secure to use?

Yes, it is secure for its users, there is no issue regarded. Millions of its users give a positive response that is why it is recommended as there is no malware and security issue. Read more:

How can I apply GB WhatsApp themes in my iPhone?

Simply open the app in your iOS and go to the GB WhatsApp setting. Themes options are available in this setting. Click on download the theme and install the theme from there. Theme will be applied on your account