Generally, Apple, Samsung and other phone manufacturers warn against using any type of cleaning agent or alcohol to clean your phone. Those products can damage a phone's protective coating.

Recently, Apple approved Clorox Disinfecting wipes or alcohol wipes with 70 percent alcohol. Samsung and other phone manufacturers have not made the same claim.

From Apple's website:

"Using a 70 percent isopropyl alcohol wipe or Clorox Disinfecting Wipes, you may gently wipe the exterior surfaces of your iPhone. Don't use bleach. Avoid getting moisture in any openings, and don't submerge your iPhone in any cleaning agent"

Apple iPhone:

General instructions for cleaning your iPhone include:

• Unplug all cables and turn off your iPhone.
• Use a soft, slightly damp, lint-free cloth—for example, a lens cloth.
• Avoid getting moisture in openings.

Apple also offers additional cleaning instructions for your specific iPhone, iPad, and Mac.

Samsung and Others:

One of the more popular methods for cleaning your phone suggests using a solution of mild soap and water on a soft cloth. Remember:

• Power down your phone. 
• Dampen a soft cloth. Do not soak it. 
• Avoid openings and ports when wiping your phone down.

Phone Cases:

Depending on the phone case material (namely leather), you should check with the manufacturer on how to clean it. For silicone cases, you can follow the following often used method:

• Mix 1/5 dish soap with 4/5 water.
• Dampen (don't soak) a soft cloth and wash the case, making sure to get into the corners.
• You can also use simply use rubbing alcohol on a soft cloth or alcohol wipes.
• Either way, make sure the case is completely dry before placing it back on your phone.

You can find phone cleaning products at local retailers and on Amazon.com.