HTC on Tuesday forecast lower revenue for the second quarter this year, trimming its profit margin guidance at the same time. The struggling Taiwan-based vendor sees revenue falling 16% from the second quarter last year to NT$105 billion, and gross profit margin is expected to slide to 27% from 28.8% during the same period a year earlier. HTC’s anticipated second-quarter revenue represents a 55% improvement over the first quarter of 2012, which saw HTC’s net profit decline sharply to its lowest point since 2006. The vendor’s new One-series smartphones recently began rolling out internationally, and both AT&T and T-Mobile will launch new HTC handsets in the coming weeks. BGR reviewed the HTC One S last week and called it the best smartphone ever to come to T-Mobile, but HTC has its work cut out for it — Apple’s iPhone 4S remains the best-selling smartphone in the world and Samsung will unveil its next-generation flagship Galaxy phone next week, just three days after HTC’s One X goes on sale at AT&T.