In DragonVale for the iPad, iPhone, and iPod Touch, the default maximum level for all dragons is level 10.
If you want to get your dragons past level ten, you’ll have to invest in dragon shrines.
Shrines start unlocking at level 18, and continue with one shrine unlocked at every level up to level 25. Each shrine costs more and more gold as well.
Each shrine has to be upgraded individually, requiring you to level up 50 dragons of that shrines element type to upgrade it.
For example, you must have leveled up 50 plant type dragons to level 10 in order to upgrade the Plant Shrine to silver, which will allow you to level up plant type dragons to level 15. After that you would need 50 level 15 plant type dragons to unlock the Plant Shrine to gold, which would allow you to level plant type dragons to level up to 20.
For this reason, hybrid dragons are extremely helpful for this, since hybrid dragons apply to multiple shrines. A Blue Fire Dragon for example would apply to both the Cold and Fire shrines.
It’s important to note also that it counts any dragons you’ve ever owned, even before you purchased the shrine, even dragons you have sold and no longer have.
Plant Shrine – Unlocked at Level 18, costs 500,000 gold
Earth Shrine – Unlocked at Level 19, costs 750,000 gold
Fire Shrine – Unlocked at Level 20, costs 1,000,000 gold
Cold Shrine – Unlocked at Level 21, costs 2,500,000 gold
Lightning Shrine – Unlocked at Level 22, costs 5,000,000 gold
Water Shrine – Unlocked at Level 23, costs 5,000,000 gold
Air Shrine – Unlocked at Level 24, costs 10,000,000 gold
Metal Shrine – Unlocked at Level 25, costs 15,000,000 gold