For new learners:
GRUFFUDD, Heini: The Welsh Learner’s Dictionary (pub. Y Lolfa)
Free App for smart-phone, i-phone, i-pad only
–
http://termau.org/index.php/install-search-plug-in/ap-geiriaduron/?lang=en
(this brings together full dictionaries and subject-specific word lists, usually recognises mutations, and is constantly updated)
On-line
http://www.geiriaduracademi.org/ (English-Welsh only)
http://www.gweiadur.com/Pawb (English-Welsh and Welsh-English, plus notes on use in phrases)
http://welsh-dictionary.ac.uk/gpc/gpc.html
University of Wales historical dictionary of Welsh (first edition –much fuller revised second edition still in preparation)– equivalent of Oxford English Dictionary
BEWARE
Google has a word and phrase dictionary which often mistranslates
e.g. te ta coffi? (= tea or coffee?) is translated as tea coffee ta
