muting the incoming call ring
A widely known but most useful tip.
If you are not in a position to answer an incoming call and just want to mute the call’s ring – press sleep/wake button once or press the volume reduce button. Eventually it will go to voicemail if unanswered.
If you want to mute the incoming call’s ring and let it go to voicemail directly without ringing further press sleep/wake button twice.
currency signs/symbols in iPhone keyboard
Keep pressing the dollar sign $ for a second or two, a pop-up will display showing other popular currency symbols – Euro, Yen, Pound

Easy way to view, copy, open URL in iPhone
Keep pressing a link in iPhone and you will get a pop-up menu displaying the full URL the link points to. It also asks if you want to open, open in new page (if the link is in safari window), copy or cancel as shown below
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