The UAE is one of the world's safest destinations for tourists. Crime rates are extremely low, and the legal system is strict — this applies both to criminals and to visitors. Be aware of local laws: public displays of affection can result in fines or arrest, drug possession (even trace amounts) carries severe penalties, and criticizing the UAE government or royal family online is illegal.
Dress modestly outside beach and resort areas — both men and women should cover shoulders and knees in malls, souks, and mosques. During Ramadan, eating, drinking, and smoking in public during daylight hours is prohibited for everyone, including tourists.