A mobile phone

Cell Phones (also known as mobile phones) are media devices mainly used for wireless communication.


Cell phone communication is a way of talking to someone when you are distant from their location. It involves sending your voice to another cell phone over a network involving many cell phone transmitters. When people are out of range of any towers, they have no signal and are in what is referred to as a "dead zone."

For demigods, at least the mortal children of the Greek gods, "cell phones transmit a message that says 'Hey, I'm right here!' to monsters," as Percy Jackson says. Using a cell phone for communication is extremely dangerous because monsters are attracted to demigod voices being sent through the air using cell phones. This was the result of a spell cast by Lamia, a daughter of Hecate who had her children killed by Hera and transformed into a monster by the goddess. As a result, most demigods communicate via Iris Messaging which monsters cannot detect or track.

Percy Jackson and the Olympians

The Lightning Thief

Percy remarks that they are going on a quest with no supervision, not even a cell phone, as calling from one is like sending up a flare to monsters.

The Sea of Monsters

After the quest, Chiron gives Percy a cell phone to call his mother on.

The Demigod Files

In the picture of Annabeth Chase's trunk, she has a cell phone that is off at all times.

Annabeth chase

Annabeth, an owner of a cell phone.

The Last Olympian

Annabeth owns a cell phone, being one of the few demigods to do so. During the Battle of Manhattan, demigods pick up a random cell phone from sleeping mortals which they use to contact the demigods who own their own cell phones, and before discarding it to avoid monsters tracking them to their exact location. They used this to keep track of enemy movements and actions. Sally Jackson gave Percy her phone in the case of an emergency during the Battle of Manhattan.

Percy Jackson also wonders if he should borrow Annabeth's phone to talk to Rachel Dare, but decides not to, because he is worried that Annabeth will get angry with him.

The Heroes of Olympus

The Lost Hero

Annabeth lends her cell phone to Piper McLean, but asks for Piper to leave it as a secret. Piper uses it to contact her father Tristan McLean, but Piper's call is unsuccessful, instead going to Tristan's secretary, Jane. During the call, Piper learns that her father has disappeared, captured by the giant Enceladus.

Magnus Chase and the Gods of Asgard

The Sword of Summer

While Frederick and Annabeth Chase are looking for Magnus Chase, Frederick looks at his smartphone to read a text from his brother, Randolph Chase.

The Trials of Apollo

The Hidden Oracle

Chiron claims that travel and communication also do not work for any of the demigods: Iris Messages and cell phones don't work, and Camp Jupiter has not communicated with Camp Half-Blood in weeks. Chiron also mentions that campers have been randomly disappearing after looking into the woods. Rachel, despite being mortal, also cannot place calls.

Known Users

Personal Weapons: Riptide | Annabeth's Knife | Backbiter | Frank's Spear | Hazel's Spatha | Katoptris | Nico's Sword | Thalia's Spear | Aegis | Maimer | Kronos' Scythe | Ivlivs | Master Bolt | Poseidon's Trident | Sword of Hades | Reyna's Spear | Hades' Staff | Juno's Gladius | Annabeth's Sword | Sumarbrander | Gungnir | Gjallar | Mjolnir | Thor's Staff | Khopesh | Mallory's Serrated Knife | Meg's Twin Imperial Gold siccae blades | Caduceus | Apollo's Golden Bow | Artemis' Knives | Ares' Sword | Ares' Shield | Thyrsus | Hecate's Torches | Minotaur's Axe | Leroy's Sword | Tyson's Javelin | Alex’s Garrote Wire
Magical Items: Annabeth's Yankees Cap | Helm of Darkness | Keys of Hades | Flying Chariot | Golden Apple | Apples of Immortality | Greek Fire | Hermes' Multivitamins | Leo's Magical Toolbelt | Nectar and Ambrosia | Pandora's Pithos | Winged Shoes | The Golden Fleece | Stygian Ice Whistle | Serapis' Staff | Magic 8 Ball | Arrow of Dodona | Pig Ball | Mechanical Spider | Angel Statues | Athena Parthenos | Chiron's Wheelchair | Diocletian's Scepter | Flaming Dodgeball | Gleipnir | Poseidon's Pearls | Queen Hippolyta's Belt | Mistletoe Arrow | Frank's Stick | Expand-o-Duck | Caligula’s Sandals | Ran’s Net
Spoils of War: The Minotaur's Horn | Medusa's Head | Kampê's Scimitars | Nemean Lion's Pelt | Gorgon Blood | Cornucopia | Lydian Drakon Hide | Phineas' Robe and Slippers
Items: Camp Necklace | Chameleon Armor | Daedalus' Laptop | Golden drachma | Denarius | Red Gold | Mark of Athena | The Pax | Video Shield | Wristwatch Shield | Golden Mango | Sibylline Books | Pillow Pet
Blessed Metals: Adamantine | Celestial Bronze | Imperial Gold | Stygian Iron | Bone Steel