NEW DELHI: Reliance Jio , the telecom arm of Mukesh Ambani-owned Reliance Industries, has extended the trial launch of its 4G services to the public through an invite system , driven by its group employees.Jio has now empowered the group employees, who had got the trial SIM earlier, to bring 10 more people to the 4G network through a referral invite system. The invite, which has to be sent by a RIL employee, will allow people to buy a LYF phone, which will come bundled with free unlimited 4G data and voice for three months.“Our state of the art all- IP TRUE 4G network is being rolled out on a massive unprecedented scale. Our network leverages technologies like VoLTE, VoWiFi….As we inch closer towards our commercial launch, we are providing our near and dear ones ( Yes you!) a chance to test out our network. Powered with rich content through various Jio APPs we intend to deliver superior DIGITAL LIFE experience to Indian consumers,” an employee invite, seen by ET, said.The 4G operator recently revealed that its services were being tested by over 500,000 users, many of whom use LYF phones. The telco had said that it will launch full scale commercial operations once the base increases to a few million users, which his widely estimated to be towards the end of this year.Under the offer, new connections will come with unlimited access to Jio applications for 90 days. Jio offers services like Jio Play, Jio On-Demand, Jio Beats, JioMags, JioXpressNews, Jio Security, and Jio Drive. “All this is for FREE. You just have to buy LYF handset,” the invite said.The extended trial will not just help the telco extensively test its network and services in the country, but will also allow it to push the sales of LYF-branded handsets, which are sourced from vendors like ZTE and CK Telecom. Reliance Jio, through its retail arm, is offering a number of devices under the LYF brand, priced between Rs 5490-Rs 19399. These LYF handsets can be bought only at Reliance Digital and Reliance Digital Mini store along with the invitation code, sent by a RIL employee over mail.Reliance Retail’s handset brand – LFY – emerged as India's fifth largest smartphone player in its first quarter since launch, creating a flutter in the world's fastest growing smartphone market which is led by Samsung, according to data from Counterpoint Research. LYF cornered a 7% share of the smartphone market in the first quarter of the year, on the back of high demand for 4G LTE phones in India where two of three smartphones shipped supported the high speed broadband services.Executives at a number of Reliance Digital Xpress stores across Delhi confirmed receiving the first lot of 4G SIM cards, besides LYF-branded smartphones, ET earlier reported."We have received Jio SIM cards but have not got any instructions from the company to sell them to public although the services are open for retail staff only, as a part of network trial," one of the Reliance Digital Xpress store managers in south Delhi earlier told ET.The telco could well stun the market, offering 0.5 paisa per 10 kb of data usage, which is substantially lower than the 4 paise per 10 Kb data being charged by India's top telcos Bharti Airtel, Vodafone India, Idea Cellular.According to SIM card kits available in Reliance Digital Xpress stores across Delhi, Jio's base tariff includes local and STD call at 2 paisa per second, Rs 1per SMS and Rs 5 for international SMS comparable with existing market rates. It also includes 5 paisa per second for a video call. To be sure, the SIM card kit is not meant for commercial sale, but gives an idea of what the rates could be like. A consumer roughly needs around 1 MB to stream an audio song, and around 440 MB for streaming a one-hour standard definition video on Youtube.