While performance of a general hatarat nedarim within days of Rosh Hashana is just a minhag,[2] it is good that you are looking for an opportunity to do it.
There is a machloket Rishonim[3] regarding whether hatarat nedarim requires the physical presence of the noder (oath taker) himself. The gemara[4] asks whether a husband can be an agent to request his wife’s hatarat nedarim and concludes that he can. Some (including R. Shimshon[5]) posit that even other people can act as agents to annul an oath, even when they are less impacted than a husband by the oath that they are trying to cancel, based on the general rule that agents can carry out halachic processes. However, the Rambam[6] is among those who require the noder’s actual presence, and this ruling is accepted by the Shulchan Aruch.[7]
How absolute is this ruling? The Keren Ora[8] and the Kiryat Melech Rav[9] suggest that the inadmissibly of an agent for hatarat nedarim is a Rabbinic law; the latter explains that the objective is to make the noder self-conscious so as to discourage him from making this a common practice. Rav S.Z. Auerbach[10] suggests that the point is to enable effective discussion of the grounds for the hatarat nedarim.
Classical poskim suggest some exceptions. The Rama[11] says that hatarat nedarim can be done through an interpreter, but the Shach[12] and Taz[13] say that this is true only when the noder is present. More significantly, the Taz[14] cites the Rashba’s ruling that even those who disqualify an agent for hatarat nedarim allow the noder to submit his request to beit din in writing. The idea is that the request must be transmitted without using intermediaries, but it works even without formalistic interaction between the noder himself and the beit din. The Taz also cites the Rivash,[15] who does not allow writing. (The Rivash’s proof is from the midrash about Yiftach’s haughty refusal to go to Pinchas to undo his oath,[16] which seems to indicate that a letter would not have sufficed.) The Taz himself does not take a clear stand on hatarat nedarim through correspondence, and the Pitchei Teshuva[17] allows it in a case of significant need.
Poskim have discussed the use of telephones with regard to several halachic matters. One such matter is the crucial issue of appointing the facilitators of a get. This is a more difficult matter than ours because of the need to ascertain identity and the likely requirement of a high level of connection between the husband and the get’s facilitators.[18] Another area of interest is berachot heard via telephone. One cannot fulfill mitzvot through such a beracha, but leading poskim have debated whether one can[19] or cannot[20] answer amen.[21] Hatarat nedarim by phone could possibly follow the same logic, or it might be more lenient (if a practical rather than formal connection between the two parties is enough) or more strict than other applications (if presence is a Torah requirement).
A Skype discussion is no worse than a written request for hatarat nedarim. After all, one’s written word does not have any special status in this context; what is necessary is simply to convey the requester’s message effectively without another person’s intervention.[22] In some ways, Skype is preferable to a written letter. It allows for give and take between the parties and creates a personal connection that could provide an increased ability to properly discuss the matter, as well as a measure of self-consciousness. In the latter regard, it might even be a slight improvement over use of a telephone. Audio/video’s greater advantage is apparent in cases in which authentication is crucial (arguably including gittin), as it is easier to impersonate a voice than a voice and an appearance simultaneously.
In conclusion, when necessary, one may rely on hatarat nedarim via Skype and even by phone.[23] We note briefly that hatarat nedarim before Rosh Hashana may require less halachic precision than hatarat nedarim for a specific oath that one wants to absolve,[24] and leniency is therefore fully acceptable when necessary.