Can I add my Quick Books to my laptop as well as my iPhone ?

Glad to have you here, dillan24.

QuickBooks Online is 100% web-based.  You can log into it on your laptop as long as it is connected to the internet. You can also download the app which also connects directly to your QB Online account. You can use this link to download the QuickBooks Online App: QBO App. You can also check out this article for detailed information about the System Requirements for your reference.

On the other hand, you can also install QuickBooks Online on your iPhone. Please note of the following: QuickBooks Mobile version 5.5 is now available to all users on iOS devices with iOS version 9.3 and greater (iPhone, iPad, and iPod touch). If you're using an iOS version earlier than 9.3, you must upgrade your device to the latest iOS to use QuickBooks mobile 5.5 or later.

Here's how to install:

1. Tap the App Store on your iPhone and sign in using your iTunes credentials.
2. Search for QuickBooks Online for iPhone.
3. Choose Free and then Install.
4. Sign in using the same QuickBooks Online company credentials.
5. Choose the QuickBooks Online company file.

If you have any other concerns about installing QuickBooks, please feel free to comment below.