Cryptocurrency can be considered as the digital money. This year can be considered as the bull year that we are seeing ATH in every week almost. So, the best time is going on for crypto. The Yahoo Finance published an article named as like the headline of this topic. I am quoting a part of that article.
Top 10 Cryptocurrency Investments in 2021
Cryptocurrency Price as of March 29, 2021 Market Cap Bitcoin $57,566.38 $1.075 trillion Ethereum $1,811.82 $209.464 billion Binance Coin $273.38 $42.304 billion Tether $0.99 $40.632 billion Cardano $1.19 $38.188 billion Polkadot $33.74 $31.349 billion Ripple $0.56 $24.598 billion Litecoin $192.88 $13.038 billion Chainlink $28.06 $11.689 billion Stellar $0.41 $9.23 billion
Cryptocurrency is a trillion dollars market now and it is getting bigger day by day. So, if you are still waiting, just look at the market volume.
I don't think Tether can be used as an investment, because you can't get profit from investing in Tether, then if you want to try your luck, so you can invest in XRP, because the price of XRP haven't increased very high in 2021 and haven't even reached its ATH price, therefore I believe if there is another bull run, then of course the price of XRP will most likely increase very high and can reach its ATH price, because people already believe to investing in XRP again and now is still the right time to invest in XRP, because the price of XRP is still cheap.