Can my application use standard extensions and still be considered compliant with the 100% Pure Java logo program?
Only if the standard extensions that you use are 100% Pure. You must submit both your application and any extensions that your application uses for 100% Pure certification. The combination of your application and all standard extensions it uses is what will be tested. 100% Pure standard extensions will signifcantly ease the testing burden, but even some standard extensions that are not certified 100% Pure may meet the requirements when combined with your application, depending on how your application uses the standard extension.
