Google Ads API.

AdWords API: Authorization for multiple users.
Here's how you handle authorization for multiple users of your AdWords API tool.
Building custom tools with the Google Ads API.
You run an digital marketing agency. You’re thinking about building a custom Google Ads tool using the API. Here are some of the things that trip people up.
Choosing a domain name for your Google Ads tool.
I bumped into an unexpected problem when I chose the domain.
Death by alerts.
Will your custom AdWords tool monitor AdWords performance? It's surprisingly difficult to work out when your monitoring system should warn your users. Read on for guidelines on alerts and notifications.
Designing custom AdWords tools.
The AdWords interface is awful. You can fix this in your AdWords tool. Here are a handful of principles to guide you as you design your custom AdWords API based tool.
How to use the Google AdWords API to do keyword research.
You’re thinking of building a custom keyword research tool using the AdWords API. Read on to see where to start and what to watch out for.
Where can I find a programmer to help implement the Google AdWords API?
Good news is that you don’t a programmer who is an expert at the AdWords API because the programming constructs that the API uses are well known. For instance, the API uses OAuth for authentication which is very common.