With growing popularity of direct messaging platforms like WhatsApp and Facebook, experts feel Twitter's decision was to keep its customers happy and the site competitive.

"Micro-blogging is the main identity of Twitter. They must be getting feedback from the users to increase the length of the direct messages from 140 characters," Rishi Tejpal, principal research analyst at Gartner, said.

"I think the Twitter decision reflects its urge to diversify into different domains using existing infrastructure," Tejpal added.

"We've done a lot to improve direct messages over the past year and have much more exciting work on the horizon.One change coming in July that we want to make you aware of now (and first!) is the removal of the 140 character limit in direct messages," one of the Twitter developers wrote.

"Twitter has been upgrading its features with a focus on its direct messaging. Lifting the limit is going to be extremely useful for brands to not only handle customer issues but in delighting customers," Sumana Samuk, digital marketing manager, Litehouse, an experience design house under Harman International.