For portfolio monitoring, I advise you to use the blockfolio, as this is a stand-alone application that does not require access to exchanges, which creates a security guarantor. I think many have already described the benefits of this application, so I will not repeat. For additional services, I would define such applications as: telegram, twitter and blockchain. This is the minimum set, which is enough for a timely response in the market of cryptocurrencies. Plus I can advise using @ ETHtokenExplorer_vot in the telegram application. It allows you to monitor the status of the MEW account without connecting to the wallet itself. In general, before using the application, I advise you to refer to official sources and check for veracity. There are a lot of fake applications that steal user data.