At least one tech founder wasn't all that impressed by what he heard during Apple's annual developers conference on Monday.

Jan Koum, the cofounder and CEO of WhatsApp, took a jab at Apple for unveiling some new features to iMessage that seem similar to those offered on his mobile messaging app.

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very flattering to see Apple "borrow" numerous WhatsApp features into iMessage in iOS 8 #innovation — jan koum (@jankoum) June 2, 2014

He didn't spell out which particular updates he was referring to, but Apple unveiled the option to insert audio, video and location information into conversations, all of which are already features you can find on WhatsApp.

Koum did not immediately respond to our request for comment.

Apple has been called out in the past for "borrowing" software features from big and small companies. It appears that tradition will continue this year.

Image: Apple

During the presentation, Apple showed that these message attachments would "self-destruct" unless the user chooses otherwise. This was billed as helping users save space on their phones, but it some have already claimed may be a threat to apps like Snapchat, which are built on that feature.

Snapchat had a more diplomatic response to this than Koum, however.

"It's exciting to see other companies begin to embrace deletion by default," a rep for Snapchat said in an emailed response to Mashable.

Messaging services weren't the only ones who noticed some familiar features from Apple on Monday. Apple also unveiled iCloud Drive, a file storage system similar to Dropbox and Box. On top of that, Apple announced better photo storage capabilities, perhaps undercutting Carousel, the photo organization app released by Dropbox earlier this year.

When asked for comment, a rep for Dropbox said the company has "nothing to share at this time." Box's CEO, on the other hand, praised Apple on Twitter for allowing iCloud to synchronize content across platforms.

The chief executives of both Dropbox and Box were reportedly in attendance at the event.