21 year-old Cryer had initially denied tweeting racist messages to Collymore following his arrest after being reported to police by the ex-footballer.
But in a hearing at Newcastle magistrates court Cryer changed his plea to guilty. He has been remanded on bail for sentencing on March 21.
Collymore made his complaint to the police on January 6 after receiving the tweets from the Twitter account @JoshuaCryer1. The former England star also re-tweeted Cryer’s posts to his 170,000 followers.
The offensive tweets ended with ‘hashtags’ including #greatracistabuse and #neitherwhitenorblack.
Collymore tweeted the following messages in response:
“@JoshuaCryer1 In the process of reporting you to Newcastle Police for racist abuse,which is in contravention of UK law.See you in court.”
“Made complaint to Northumbria Police who’ve just passed it to Staffordshire Police. Ive got screen shots of every message,his fb page”
“>his Newcastle Law School details,and photo. Not having this **** anymore.”
“Joshua, I see you’ve deleted your tweets.I haven’t.”
A message was later posted from the @JoshuaCryer1 account, denying the allegations and suggesting the tweets had been made by somebody else.
It said: “@Stan Collymore apologies for all the abusive tweets just been notified about it these do not represent my views. #notafunnytwape”
Then the Twitter profile @JoshuaCryer1 was deleted.