Shelley's Incentivized Testnet will allow ADA holder to earn ADA through staking. Shelley's Incentivized Testnet on 9 December.
The balance snapshot was taken on November 29 at 12:00 UTC at epoch 159, slot 6886. If you had ada in a mainnet Daedalus or Yoroi wallet at the time, you will soon be able to delegate your stake to earn real ada rewards on the Incentivized Testnet.