Why is yahoo mail useless on my ipad?

i can't use my yahoo email on my ipad. when i try to open an email, it says i need flash 9 - ipad doesn't have flash. When i do get them to open I can't scroll down on the touch screen to actually READ the email. When i put emails in the trash and then EMPTY the trash, when i go back to my inbox the emails are all there again. Useless. There's an app for iphone, why not ipad?