China Mobile Ltd. added about $21 billion of market value in Hong Kong after the firm reported increasing adoption of its 4G services.

The world's biggest wireless carrier surged 7.5% to HK$115.9 at the close of trade, the biggest gain in almost six years. In the first quarter, China Mobile added 53 million users to the 4G network. The carrier reported that 143 million customers are now on the high-speed network.

The company has confronted increased costs to build its 4G network and attract users with promotions on tariffs and smartphones. According to Anand Ramachandran, an analyst at Barclays Plc, declines in average revenue per user have hit bottom after the first quarter result.

In a report to clients, Ramachandran wrote, "Rising 4G adoption should sustain ARPU rises and thus revenue momentum. Rekindled momentum from 4G should allow China Mobile to return to growth".

The Beijing-based company's net income dropped 5.6% to 23.8 billion yuan ($3.8 billion) in the first quarter. Sales rose 3.9% to 160.9 billion yuan.

The carrier reported 815.4 million subscribers as of the end of March, up 8.75 million from the end of 2014. The company said that the average revenue per user was 59 yuan a month, up from 58 yuan reported in the fourth quarter.

The wireless is set to report its earnings for the first quarter of fiscal year 2015 tomorrow.