SAN FRANCISCO — Google on Thursday said it will be keeping a tight grip on its Honeycomb software crafted specially for tablet computers. The California technology giant, known for letting outside developers and gadget makers have their way with its Android software for powering mobile devices, wants them to keep their hands off Honeycomb for a while. Google optimized Android 3.0, known as Honeycomb, for champions fielded in a tablet arena dominated by Apple iPads and was concerned that it might wind up used in smart phones where it wouldn’t shine. “Honeycomb was designed from the ground up for devices with larger screen sizes and improves on Android favorites such as widgets, multitasking, browsing, notifications and customization,” a Google spokesman told AFP. “While we’re excited to offer these new features to Android tablets, we have more work to do before we can deliver them to other device types including phones.” Google planned to release Honeycomb as “open source” code for developers and gadget makers “as soon as it’s ready,” according to the spokesman.