Donald Trump may claim "I know words, I have the best words" — but when it comes to his Twitter account, how many of those words actually his?
One computer programmer made it his personal mission to find out.
David Robinson, a data scientist at Stack Overflow, determined that the angriest tweets from Trump's official Twitter account, @realDonaldTrump, were sent from an Android device — while more moderated messages that focused on events and campaign strategy were sent by an iPhone.
Members of the Republican nominee's campaign staff are known to use iPhones. However, Trump uses a Samsung Galaxy, having sworn off Apple after that company's battle with the FBI over unlocking the phone of one of the San Bernadino attackers.
Read More: Where Hillary Clinton, Donald Trump Stand on Tech Issues
Looking only at tweets sent from an iPhone or Android device, Robinson's analysis showed there were distinct differences between the types of tweets sent from the two devices, including style, tone and the time of day.
"Since other people had noticed this phenomenon before, I did expect to find that the accounts showed different behaviors," Robinson told NBC News. "But I was surprised how dramatic the difference was, particularly regarding the use of hashtags, photos, and links."
RELATED: Trump Responds to Criticism of 'Star of David' Tweet
Tweets from the Android phone were mostly sent in the morning and included emotionally charged words such as "badly," "crazy," "weak," and "dumb."
A sentiment analysis revealed Trump’s Android account uses about 40 to 80 percent more words related to negative feelings than the iPhone account.
Does the Android user, who Robinson says must be Trump, wake up on the wrong side of the bed and fire off his angry tweets before he calms down and switches to an iPhone in the afternoon?
While anything is possible, Robinson said there is a clear distinction that shows at least two different people are sending tweets from different phones to Trump's account.
RELATED: One Year of Donald Trump's Tweets, Analyzed
The iPhone tweets come in the afternoon and early evening and include messages heavy with campaign hashtags, such as #trumptrain or #makeamericagreatagain. They were also 38 more times likely to contain a photo or link, Robinson said.
Trump's tweets have been the target of particular scrutiny during his presidential campaign, due to frequent and egregious misspellings. After the February 25 Republican debate, he twice tweeted that then-challenger Senator Marco Rubio was a "leightweight chocker" (those tweets since deleted). Trump has also mangled the spelling of several American cities, including Phoenix, Tulsa, and Oklahoma City; and even misspelled Barack Obama's name. Twice.
The Trump campaign did not immediately respond to NBC News' request for comment.