Can you link me to some of these apps that let you write code on the phone itself?  (Preferably Android, as that&#x27;s what I have.)  I haven&#x27;t actually used any, and I&#x27;m curious.<p>But the important point is -- the phones don&#x27;t <i>come</i> with them.  The TI-82 literally had a button that you&#x27;d press to access programs, and the submenu within was &quot;Run&quot; or &quot;Edit&quot;.  That discoverability was very important.  The kinds of people who would search for and use apps to write programs on the device are the kinds of people like us, who don&#x27;t need it.  (I do all my Android development in Android Studio on a workstation, for obvious reasons.)