The best alternatives to InstaLogin are MailDrop, Landmark, and InboxKitten. If these 3 options don't work for you, we've listed a few more alternatives below.
This mobile client for Maskmail enables you to create unlimited disposable email addresses forwarded to your inbox in order to give them around instead of your real email address.
IdBloc protects your privacy & security by generating permanent, anonymous email addresses on demand. Use IdBloc whenever someone wants your email address. Emails are automatically forwarded to your real address, keeping your identity secure.
Never give your private email away again. CatchMailNot lets you replace your real email address with unlimited custom addresses. Find your busiest aliases using our statistics, then create rules and filters to manage your workflow.