Embracing innovation and technology is giving Ukraine an advantage, writes Jonathan Beale. Its air defence capabilities during more than four years of war with Russia have become increasingly sophisticated. In the beginning, it was relying on a network of mobile phones attached to telegraph poles to listen out for the sound of approaching drones. Now it has a system, Sky Map, which uses thousands of sensors and AI to detect threats and guide its air defences. And one weapon, more than any other, is helping to take down Russian Shaheds: cheap interceptor drones. They are 3D-printed and cost a fraction of the price. But there are still glaring gaps in Ukraine's defences. In one 48-hour period last week, Moscow fired 1,500 drones and 56 missiles, one of which hit a Kyiv apartment block, killing 24 people. By launching such heavy waves of strikes, it's inevitable some will make their way through, Jonathan says, although the loss of life could have been even higher.