What are some alternatives?
When comparing Uphold and Kraken, you can also consider the following products
Coinbase - Bitcoin, safe and easy.
Electrum - Electrum is an easy to use Bitcoin client.
Bitfinex - Bitfinex is the largest and most advanced crypto-currencies trading platform.
Binance - Cryptocurrencies exchange platform
LocalBitcoins.com - LocalBitcoins.com is a person-to-person bitcoin trading site.
Exodus - All-in-one app to secure, manage and exchange blockchain assets.