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Description
Toepads are something that has evolved many times in different frog lineages so it is no surprise that it would evolve on the Frog Planet as well. With the recent evolution of trees there has been an explosion of tree frog diversity all over the planet, but some of these "tree frogs" actually existed before trees. To give a quick lesson, toepads work using wet adhesion. There are little tiny nanopillars on the pads that form around the surface the frog puts their fingers on, and then mucus from specialized cells fill in the empty spaces and make a strong seal. Drainage around the cells constantly clean the mucus to prevent debris from clogging or getting stuck.

1. This is a primitive proto-tree frog. It does not have toe pads, but its fingers are longer and flexible for gripping. The intercalary elements, which are ossified in swimming frogs for strength, have been reduced to flexible cartilage to allow the fingers and toes to move freely. They have also lost their webbing in their hind feet. Their small size allows them to climb up vegetation such as grass and fit into small spaces.
2. This is another tree frog that came before trees, and is also a primitive lineage. Their toepads evolved to allow them to scale tall rock faces and cliffs. They live in small caves near steep streams and waterfalls, and contrary to other frogs they breed during the dry season when these streams are calmer. Their tadpoles have sucker mouths to allow them to graze on algae in the fast flowing water and climb up the waterfalls.
3. Finally a proper tree frog that spends its life up in tall vegetation. This is a baby with its green color and white stripe allowing to camouflage on grass, but adults will become a mottled brown as they transition to living on woody shrubs and trees. It is a typical tree frog, eating bugs and waiting for rain so it can lay its eggs in puddles of water.
4. Another tree frog, except this one lives at the very top of tall trees in wet tropical climates. Its hands/fingers have evolved into a right angle to give them an incredibly strong pinching grip on the thin branches the climb around on. This is a feature already present in Earth frogs, such as the genus Chiromantis. During the wet season they descend down to the forest floor and breed in a giant frenzy, with other frogs and predators taking advantage of this to either eat them or their offspring.

Then we have the burrowing frogs. There are two types of burrowing methods in frogs, backwards and forwards. Backward burrowing frogs dig using their hindlegs and are characterized by large eyes and blunt snouts. Forward burrowing frogs have strong forelimbs, a pointy head shape, and smaller eyes. The forward burrowers are more adapted to the burrowing lifestyle and usually dig deeper than the backwards burrowers.
5. This is a typical backward burrowing frog. It has a fat round body to help it survive periods of drought in its dry environment. At night time they ascend to the surface to hunt insects before going back underground at sunrise. On their hind leg is a small keratin structure that acts as a shovel when digging.
6. This is a typical forward burrowing frog. Its pointy head and thick forelimbs allow it to dig through soil but it does not dig as deeply as other members of its family, still coming out to the surface at night (though it lives in tropical climates unlike the previous frog).
7. This a forward burrowing frog as well, but they dig much deeper. They rarely come to the surface as can be seen with its tiny eyes and stout body. Instead, they try to unearth worms and the larvae of beetles, and if they are lucky they will break a hole into a colony of crickets or beetles where they will just sit with its head sticking through the side of the wall, eating any insect that walks by. They only come above ground to breed before quickly disappearing once more.
8. This is a burrowing clawed frog, but it is strange in several ways. It is both a forward and backwards burrower, with strong forelimbs and the claws on their hind legs allowing them to break apart dirt, but if you look at their hands you will see toepads like a tree frog. This is because the clawed frog does not have a tongue and without water to create a vacuum into their mouth, they needed to evolve a way to efficiently capture prey. These toepads are covered with sticky mucus much like a frog's saliva and help the clawed frog latch onto any crickets or beetles it may come across. These toepads would obviously get dirty, especially underground when the frog is digging, so the mucus cells are able to close themselves and stop until needed. Another issue is that without a vocal sac it is hard to vocalize on land (clawed frogs vocalize by snapping a bone in their throat), so the frogs need to go underwater to sing and find their mates.

Description
Toepads are something that has evolved many times in different frog lineages so it is no surprise that it would evolve on the Frog Planet as well. With the recent evolution of trees there has been an explosion of tree frog diversity all over the planet, but some of these "tree frogs" actually existed before trees. To give a quick lesson, toepads work using wet adhesion. There are little tiny nanopillars on the pads that form around the surface the frog puts their fingers on, and then mucus from specialized cells fill in the empty spaces and make a strong seal. Drainage around the cells constantly clean the mucus to prevent debris from clogging or getting stuck.

1. This is a primitive proto-tree frog. It does not have toe pads, but its fingers are longer and flexible for gripping. The intercalary elements, which are ossified in swimming frogs for strength, have been reduced to flexible cartilage to allow the fingers and toes to move freely. They have also lost their webbing in their hind feet. Their small size allows them to climb up vegetation such as grass and fit into small spaces.
2. This is another tree frog that came before trees, and is also a primitive lineage. Their toepads evolved to allow them to scale tall rock faces and cliffs. They live in small caves near steep streams and waterfalls, and contrary to other frogs they breed during the dry season when these streams are calmer. Their tadpoles have sucker mouths to allow them to graze on algae in the fast flowing water and climb up the waterfalls.
3. Finally a proper tree frog that spends its life up in tall vegetation. This is a baby with its green color and white stripe allowing to camouflage on grass, but adults will become a mottled brown as they transition to living on woody shrubs and trees. It is a typical tree frog, eating bugs and waiting for rain so it can lay its eggs in puddles of water.
4. Another tree frog, except this one lives at the very top of tall trees in wet tropical climates. Its hands/fingers have evolved into a right angle to give them an incredibly strong pinching grip on the thin branches the climb around on. This is a feature already present in Earth frogs, such as the genus Chiromantis. During the wet season they descend down to the forest floor and breed in a giant frenzy, with other frogs and predators taking advantage of this to either eat them or their offspring.

Then we have the burrowing frogs. There are two types of burrowing methods in frogs, backwards and forwards. Backward burrowing frogs dig using their hindlegs and are characterized by large eyes and blunt snouts. Forward burrowing frogs have strong forelimbs, a pointy head shape, and smaller eyes. The forward burrowers are more adapted to the burrowing lifestyle and usually dig deeper than the backwards burrowers.
5. This is a typical backward burrowing frog. It has a fat round body to help it survive periods of drought in its dry environment. At night time they ascend to the surface to hunt insects before going back underground at sunrise. On their hind leg is a small keratin structure that acts as a shovel when digging.
6. This is a typical forward burrowing frog. Its pointy head and thick forelimbs allow it to dig through soil but it does not dig as deeply as other members of its family, still coming out to the surface at night (though it lives in tropical climates unlike the previous frog).
7. This a forward burrowing frog as well, but they dig much deeper. They rarely come to the surface as can be seen with its tiny eyes and stout body. Instead, they try to unearth worms and the larvae of beetles, and if they are lucky they will break a hole into a colony of crickets or beetles where they will just sit with its head sticking through the side of the wall, eating any insect that walks by. They only come above ground to breed before quickly disappearing once more.
8. This is a burrowing clawed frog, but it is strange in several ways. It is both a forward and backwards burrower, with strong forelimbs and the claws on their hind legs allowing them to break apart dirt, but if you look at their hands you will see toepads like a tree frog. This is because the clawed frog does not have a tongue and without water to create a vacuum into their mouth, they needed to evolve a way to efficiently capture prey. These toepads are covered with sticky mucus much like a frog's saliva and help the clawed frog latch onto any crickets or beetles it may come across. These toepads would obviously get dirty, especially underground when the frog is digging, so the mucus cells are able to close themselves and stop until needed. Another issue is that without a vocal sac it is hard to vocalize on land (clawed frogs vocalize by snapping a bone in their throat), so the frogs need to go underwater to sing and find their mates.