by Pauline TALAGRAND PARIS, France (AFP) — Smartphone app Telegram, favored by the Islamic State group thanks to the encrypted messaging it offers, is proving a headache for French anti-terror investigators. The free-to-download instant messenger, which allows people to exchange messages, photos and videos in groups of up to 5,000 people, has attracted some 100 million users since its launch in 2013. And there are a couple of features that make it particularly attractive to […]