Today my iPad is broken, so I cannot see the display on the screen properly. I will still try to type this post.
Hi Molly. Good job! A few hours ago, as you were trying to type on your iPad back then, at that moment, you should write that it IS broken. The words "is," "see," and "am," (especially when used with "today") all show present tense. Similarly, the word "trying" shows present continuous tense when paired with "am." Thus, you meant as you were writing/trying to write your post.
Using the word, "was," would change the rest of your sentence (Today my iPad was broken, so I could not see the screen properly. I was trying to type a post). The word “so” can be many parts of speech, but in this case, it is being used as a conjunction to connect two independent sentences. Therefore, you need to put a comma before it (and I know that I told you this before...!) Yes, you need to be more strict with yourself! (*-^)