Leona Lewis massively kicked off her new era earlier this year and her comeback was promising beforehand, as she’s now under Island and Def Jam. The former X Factor winner has now premiered another couple of singles, one for the American market and another for the rest of the world.Stateside, the songstress will be releasing “Thunder” on July 27 and it will be her first single in the market since 2009′s “Happy”. Leona Lewis teamed up with Toby Gad to craft this one and the two deliver a stunningly empowering midtempo. The simplistic yet fitting production compliments her insanely good voice, making the track yet another great offering from the upcoming record. Give it a listen below.In the rest of the world, the title track “I Am” will be the one getting the single treatment. Leona Lewis once again collaborated with Toby Gad, along with Francis White. The track serves as a post-break-up, self-empowering ballad that could very well be her middle finger to former label boss Simon Cowell. It’s beautifully sung indeed, but there’s no doubt that it could have been so much more overall. Check it out for yourself.“Fire Under My Feet” did serve as the lead single in the United Kingdom, so “I Am” is actually a follow-up to it. “Thunder” will serve as the lead single in the United States, which is quite a shame considering she could try the criminally underrated “Fire Under My Feet” first. All of the singles are included in the songstress’ forthcoming, fifth studio album, I Am. Leona Lewis is expected to release the record on September 11 in the U.K., and even though no Stateside release date has been announced yet, it will probably be around the same time.