Is it forbidden to show off one's mobile phone to people out of a feeling of arrogance or disdain?

The blameworthy arrogance (kibr) is belittling people and rejecting the truth, as the Prophet, peace and blessings be upon him, said: "Arrogance is rejecting the truth and despising people." Owning valuable possessions and having self-respect are not included in this. Elevating oneself in the presence of the arrogant and showing independence from people are meanings that are desirable, both Islamically and rationally, as long as they do not lead to the forbidden arrogance or ill-manners.