Breaking old habits is hard but sometimes worth it. Is opening a bunch of background tabs a really efficient way of doing things? On a PC it works if you have a high enough resolution to display all the open tabs and enough RAM/CPU to quickly switch between them. On mobile devices it pays to focus on more efficient ways of doing things because you're dealing with limited resolution, potentially slower 3G networks, limited CPU/RAM/battery, etc. That being said there are browsers on the App Store that support tabs.