I'm learning Spanish and have dabbled in other languages like Russian and Mandarin as well. I use Duolingo, but not on my phone. The website is relatively accessible, although maybe a bit tricky.

I also use a course called Language Transfer that is completely audio based and free. It's really excellent and there are courses for a few other languages like French, German, Italian, Swahili and Egyptian Arabic as well.

If you are a Windows user I suggest installing Instant Translate add-on on your copy of NVDA. It can help you later on when you try to read complicated text. The Quick Dictionary add-on would be useful as well, although currently the dictionaries it uses aren't all that comprehensive. Also, if you are learning a language that doesn't use the Latin alphabet, you can use Dual Voice add-on to make NVDA automatically switch SAPI5 text to speech engines for reading English and the other language. Vocalizer Expressive on JAWS and NVDA does that too. Finally if you use a braille display the Braille Extender add-on can be useful. It, for example, lets you quickly change braille output tables.

If you need to read phonetics, there are ways to enable JAWS or NVDA to do so for you. Good luck.

I improved Englisch (second language) from grade school (i started it as very low sight person) in meantime my vision worsened to legally blind to C1 level I went to university to study English and to be a translator. Didn't worked out because I lacked skills in Braille. 10 years ago there were no apps to sell learn I used scanned enlarged books, PDFs, lectures, audiobooks, YouTube was scarce much better was using live people much more productive and effective :) some even shared nites with me.

My third language German (as legally blind) I learned from scratch - with 1 - 1 German teacher so fast that after 3 years i could write final high school exams in basic level. It was lot of memorizing, speaking, I was writing texts on win 7 computer using narrator and wordpad but my exams were spoken only there were no written part i had to answer all questions but in a different way. I achieved B1-2 level in German.

I learned some medical latin as physiotherapist (school, lectures, files from others and internet, medical books, dictated, braille), some words in Portuguese, Spanish for occasional travel

Bear in mind advantages and disadvantages of new solutions although free and accessible they're not perfect at all.
Google Translate and similar is ok for single words between my native language and other ones but for more complex stuff it's totally useless - i tested it and Duolingo, Babel, PONS, Tandem how do we: my and my German native language teacher would understand each other based on results from the apps. It were simple sentences but apps had huge problems with grammar, results often lost quite lot of sense after translation very disappointing.
There's no shortcuts and trough those apps you can't really learn languages well, there's lots of good language learning elements missing our and those aren't correcting you properly as a real teacher would. Real teachers are more flexible and accessible in my experience lots of apps were graphic and inaccessible not enough time to answer. If i had a question app can't explain a teacher can do it it can catch errors that i wouldn't notice and correct them prevent from memorizing them.

Even a native speaker, tandem partner that's not trained for learning others in learning foreign language isn't as good option as a teacher. Sure it would add you courage to speak but extremely often such people just only speak with you and don't correct your grammar/speaking mistakes they're not trained for it. They often teach you slang/dialect/regional words which isn't always good if you want to learn language properly later for school or work and then later in other region others wouldn't understand you.

I would like to learn to speak Spanish for work. I learned in school, but I haven't used it in a while so forgot a lot of it. I was thinking of using Duolingo or Babbel to refresh my skills. I work a call center in Florida and a lot of people call asking for Spanish speakers and it's hard to get someone to talk to them so wanted to learn for the sake of some of these callers.

I was planning to ask this myself.

My native language is Spanish, and I would like and need to learn English.

But I don't even know where to start, besides some things about the language frustrate me. Why do you speak differently from how you write? Aaaahaha damn irregular words!

Some native Spanish speaker or someone who knows English, any advice please?

Memrise is accessible on the iPhone.

Duolingo is completely accessible. I wouldn’t say it’s a substitute for other language learning processes, but I picked it up after I lost a lot of my Spanish-speaking abilities due to lack of use, and I currently have something like a 310 day streak going.
Edit to add that I mainly use it on my iPhone.