MOSCOW, Aug 24 (Reuters) - Russia is using new digital hardware to target an online app that jailed Kremlin critic Alexei Navalny"s team created to undermine the Kremlin at next month"s parliamentary elections, cyber experts said. Navalny and his allies want to use the app and their website to organise a tactical voting campaign at the Sept. 17-19 vote to land a blow to the ruling United Russia party that dominates the political landscape. The "smart voting" campaign requires followers to sign up and be allocated a candidate who is judged to have the best chance of defeating the party in their election district. read more It is one of Navalny"s few remaining levers after a crackdown banned his movement as extremist this summer. Several of his websites have since been blocked. Communications watchdog Roskomnadzor has told Google and Apple (AAPL.O) to remove the app from their stores. read more Neither has done that so far and the app has been trending in Russia"s online segment. Late on Monday, Navalny"s allies accused Russia"s authorities of moving to block it, efforts they said had intensified since Friday and meant the app was not loading content for some users. "We"ve fixed some things and now the accessibility of the app is around 70%," his allies said on Telegram messenger. GlobalCheck, a group that monitors the accessibility of websites in Russia and the region using sensors, said Russia was disrupting the app with equipment that uses a technology called Deep Packet Inspection, which can analyse internet traffic, identify the data flows of particular services and block them. Russia"s communications watchdog ordered all internet providers, including mobile operators, to install that equipment in 2019 after Russia passed legislation known as its "sovereign internet" law. The legislation was one of a series of moves by authorities to tighten internet controls that stirred fears among internet freedom advocates that Russia was tacking towards a stricter China-style vision of internet control.