Andre of Astora is a very skilled blacksmith who can be found in the Undead Parish.
Andre can upgrade weapons with Titanite, ascend weapons to give them elemental properties, and repair equipment. Andre also has a fair amount of wares to sell to the player, including Titanite Shards, the Crest of Artorias (needed to open a shortcut in Darkroot Garden), the Reinforcement Kit, the Repair Kit and a Bottomless Box. The Bottomless box, Repair Kit and Reinforcement Kit can all be used at any Bonfire. Like all blacksmiths, Andre can be given certain kinds of Embers found during the player's journey that will allow for weapons to be reinforced and upgraded even further.
The game's director, Hidetaka Miyazaki, has stated in interviews that Andre was originally intended to be the banished firstborn son of Gwyn, but the idea was scrapped during the game's development.
Dark Souls III
Andre makes himself immediately available to the player with his smithing station conveniently located in Dark Souls III's central hub Firelink Shrine.
He can upgrade and repair weapons and shields, but this time requires nothing more than Titanite of varying degrees of rarity to reinforce such equipment to the highest level.
He can also infuse weapons and shields to take on special properties using gems. However, he has to be given specific coals to perform more advanced types of infusions.
While he no longer sells wares, he now has the ability to reinforce the player's Estus Flasks with Estus Shards, as well as allot the number of shared uses between the Estus Flask and Ashen Estus Flask.