Your Deskjet 3050A is Airprint compatible for the iPad and definitely usable on your Macbooks.
If you have the latest OS X Mavericks, follow this link for detailed instructions: http://h10025.www1.hp.com/ewfrf/wc/document?docname=c03967522&cc=us&dlc=en&lang=en&lc=en&product=5061092
Otherwise, use this guide: http://h10025.www1.hp.com/ewfrf/wc/document?docname=c02722113&cc=us&dlc=en&lang=en&lc=en&product=5061092#N1797
Best Regards.
If you have the latest OS X Mavericks, follow this link for detailed instructions: http://h10025.www1.hp.com/ewfrf/wc/document?docname=c03967522&cc=us&dlc=en&lang=en&lc=en&product=5061092
Otherwise, use this guide: http://h10025.www1.hp.com/ewfrf/wc/document?docname=c02722113&cc=us&dlc=en&lang=en&lc=en&product=5061092#N1797
Best Regards.