How can I convert an executable to a format Android phones can read?

Q. Most Android applications are written in Java, but I will use something else... I have no trouble of making the EXE file but can someone please tell me how to convert it to a file Android can read?

A. Android system does not understand PE format. so called windows exe files are in this format (PE stands for Portable Executable but it is not so portable after all!). likely Android executable frmat is ELF, a well-known widely used (among several systems) "codes container".
moreover, the code into windows executable files is for x86 processors (or for CLR, not JVM), and Android hardware for sure has no x86 processors and afaik no x86-opcode compatible processor too.

so basically, it's nonsense "converting" an exe (specific format, specific system, specific machine code for specific processor, specific library bindings) into "a file Android can 'read'" (oh, as passive data you can transfer the exe to android as it is, but forget it can run it or even "see" that there's code inside! just data to it!)

What is the best dictionary to download on android phones ?

Q. I have a HTC Desire HD that is android 2.3.3 and I am looking for the best dictionary for Android. I find it more time consuming to use the normal dictionaries.

A. Dictionary.com is the best.
https://play.google.com/store/apps/details?id=com.dictionary&hl=en&referrer=utm_source%3Dgoogle%26utm_medium%3Dorganic%26utm_term%3Ddictionary+android+app

Merriam webster is also good.

https://play.google.com/store/apps/details?id=com.merriamwebster&hl=en&referrer=utm_source%3Dgoogle%26utm_medium%3Dorganic%26utm_term%3Ddictionary+android+app

How do Android phones update to the newest firmware?

Q. I have an HTC Aria. I know how iPhones upgrade a stuff, but I don't know how Androids update. Do the phones just update themselves when there's a new firmware? Thank you in advance.

A. yes they update themselves wirelessly- you will receive a notification on the phone when an update is ready to install