Shawn Mendes achieved some level of success on his debut "Handwritten" despite the mixed reviews from critics. However, his second album "Illuminate" made him a more successful singer as it was well-received by critics as well as fans, giving the album better sales.
"Illuminate" was led by the pop track "Treat You Better", a song which reminded me of "Cheap Thrills" by Sia and "Shape of You" by Ed Sheeran on its intro. Still, the song became a hit on its own right. It reached number 6 both in UK Singles Chart and Billboard Hot 100, and number 3 on Mainstream chart. It has achieved 6x platinum and 3x platinum in US and UK respectively. As of this writing, it has exceeded 2.3 billion views on YouTube.
Shawn Mendes/YouTube
"Mercy", which was initially released as a promotional single, was eventually released as the second single off "Illuminate". It was a number 15 hit in Billboard Hot 100, where it was a 4x platinum awarded in the US. In UK, it also peaked at number 15, and was 2x platinum. It had more than 400 million views already in YouTube.
"There's Nothing Holdin' Me Back" became the final single from the album after its re-issue. It was an international hit, reaching the top 10 in many countries including the UK at number 4, and was 3x platinum, and the US at number 6, and had gone 5x platinum. It has achieved 1.2 billion views on YouTube.
Shawn Mendes/YouTube
"Illuminate" became Shawn Mendes' second number 1 in the US, and had gone 2x platinum there. It reached number 3 in UK, where it was platinum.