Which of the following is NOT true about mobile app development?

a$.$

Many experimental features and A$/$B tests are more easily conducted on the Web than on mobile.

b$.$

Updates and bug fixes can take longer to reach mobile users than users of a firm's web product.

c$.$

A well$-$designed app can increase an e$-$commerce site's customer engagement since customers always have the "store" in their pocket.

d$.$

Mobile apps are considered far easier to develop than websites, in fact, most managers can create robust apps using drag$-$and$-$drop tools.

e$.$

All of the above are true.