When you are trying to delegate your ATOMs, you can use "Lunie" which is the official web wallet for Cosmos. Currently, you can only use Lunie with Ledger Nano S () to delegate, send or withdraw rewards. The other way is using a 3rd party wallet made by "COSMOSTATION" mobile wallet. COSMOSTATION wallet supports both Android and iOS versions. For further information, please refer to the links below.