Altcoins that I will write below will have some important events. If you have these altcoins, it will be useful for you to keep track of them.
1. Flow (FLOW) - Stake rewards distribution
2. Swipe (SXP) - Debit card delivery
3. Stratis (STRAX) - commissioning InterFlux
4. IoTeX (IOTX) - 90 million IOTX will be burned
5. Ankr (ANKR) - ONX airdrop to be made : Will be in the ratio of 1: 10,000